Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing My continuing GDI saga, and its not good news.

I've been spannering since the age of seventeen. Back then it was crude spannering. But I have never been beaten, until now. OK, fancy management systems are right up there and I'm a lot happier with a pair of SUs, and a timing light.

Morgan, in their wisdom have locked out the GDI ECU. Even my Son in Law, with cutting edge fault readers can't get in.

So into the story.................................................................................................

In a post to match and even exceed those of Luddite..............

In the spring of 2024, we did a Highlands road trip in our GDI, covering over 1,000 miles in 8 days and it was as it has always been, without any problems. It was eight years old . The MoT from 2019, at three years old, was always close on emissions at 2.500rp, against the clock, but my tester at the village garage was patient. Sometimes taking a few goes to get it under the limit. The tailpipe was black from new and the throttle was hair trigger. In the autumn of 2019 I fitted the AR manifold and exhaust, and the factory added the AR flash to the ECU. The throttle response steadied down, and the tailpipe improved somewhat.

In the autimn of 2024, without a lot of use after Scotland, on an early morning run, I encountered the story I have already related on TM. After about ten miles, the power went down like a slider control to just tickover, and nothing more. The engine started normally and idled normally, but would not rev at all. After a lot of throttle flooring, and sporatic sudden high revs, it cleared, and we ran normally to the filling station and I filled the tank. On the run home it repeated this about five times, but we made it home, and as I put it into the garage, the problem vanished. I later discovered that a couple of other GDI owners have had similar faults in hot weather, which appeared and vanished suddenly. One could manage a slow speed until it cleared.

Cars don’t heal up. I told MrsW that without finding out what was the cause, it would inevitably return. I changed the relays, checked the earths. Checked the MAF, and that was it. By the summer of 2025, my village tester had retired, and I had also been off the road for a while after my TIA stroke. I concluded it best to use my nearest dealer, but MrsW had to drive there. Sadly it failed dismally on emissions. I was beginning to suspect the catalyst was at fault, and so I commissioned a replacement, although finding an exhaust specialist interested in doing this was a challenge.

In October 2025, we returned to the dealer with an upgraded catalyst and new O2 sensors, and it failed dismally. The rich mixture was off the scale at 2,500rpm. After discussing options, we concluded that the dealer should replace the AR flash with the standard one, although I could not restore the AR flash without paying again. This last throw of the dice worked, and it passed the emissions. But the hair trigger throttle was back and so was the black tailpipe.

A few weeks ago, we were out on an early morning run. After about twenty miles, I, and MrsW, sensed a hesitation when revving, and as we turned for home, it got progressively worse, but thankfully the traffic lights were kind, and we managed to get home. Back on the drive, the tickover sounded super rich. A very regular pulse, of brum-brum-brum-brum, although the revcounter was reasonably steady, and the engine sounded reasonably steady when listening under the bonnet. After about a minute, the tickover returned to normal, but it would not rev cleanly at all. It was very similar to what happened the first time.

I expected that the plugs would be a wet mess. They were bone dry and clean. First job was new plugs. I didn’t expect new plugs to make any difference, and they didn’t. Then new coil packs, from Autodoc. These are fancy Bosch coil packs but when fitted, it would not start or even attempt to fire. I have heard that if the fuel pressure doesn’t fall within parameters, the plugs don’t fire, but this was unexpected. So I got a cheap set of unbranded coil packs off E Bay, and it would start but no change to how it ran.

Now it starts to get difficult without being able to look for fault codes, but of course MMC locked off the GDI ECU to dealers only. So I’m a long way from any dealer with an undriveable GDI. I decided to try one final thing. BHM have had a couple of GDIs with fuel pump issues. I ordered a fuel pump. BHM didn’t have one and neither did Morgan, so that took a couple of weeks to arrive. Fitting a fuel pump into a GDI is a challenge. This will vary across models because the tanks changed shape. But the problem with mine, is the the tank unit is tall, and clearance is not. Over the top of the pump is an ash crossbrace. So either that comes out, or you drop the tank. Such fun. The ash crossbrace thankfully is not glued, but has two crosshead screws at each end, buried under the slope of the cockpit rear panel, and the edges are covered by the trim panels which are glued in place. The only way, is to use an offset screwdriver in the confined space and take each screw out, basically at a quarter turn a time. Under the spare wheel aperture, is about six wood screws. Then peel back the trim, and attempt to free off the ash crossbrace. It eventually gave way. The pump is complex and includes the sensor, but only has a single electrical connection and the output pipe, which is held in place by a sneaky and rather fancy ‘C’ clip. After freeing off the rather large plastic ring fastener, and freeing off the rather fancy rubber seal, the pump then lifts out with a pint of petrol going everywhere. Obviously before any of this happened, I disconnected the battery. The new pump then slots in, noting the correct position, and I lubricated the seal with a smear of vaseline, because it is ribbed and a rather tight fit. A torch inspection of inside the tank showed nothing unusual. No contamination of junk, and no trace of water globules.

After re-assembly, I was rather disappointed that on starting, there was no change, and I began to realise that it was time for the experts. Finally, I tried a new relay, the one which resides under the spare wheel, and that made no difference. So here’s the thing. The fuel pump in the tank is a conventional low pressure pump. It’s a bit fancy because there is a solenoid in there, but it’s not the high pressure delivery which the GDI needs. The high pressure pump is mechanical and is driven off the offside camshaft. From the high pressure pump, there is a steel fuel pipe which feeds the fuel rail on the nearside of the engine and this is where the injectors are. The high pressure pump has a bleed return to the tank, controlled by a solenoid on the pump. This solenoid is controlled by signals from the crank sensor, the cam sensors, and the ECU, which will be compiling a load of data I guess, about speed, throttle position and O2 sensor readings, and probably more. Something in that system is faulty. It might be the connection between the accelerator and the throttle body, but without looking at the error codes, I could end up changing everything and still not find out what’s going on.

So today, BHM picked up my GDI, which could barely reverse up the drive. I will post pics soon. Darren Church, who runs 468 Logistics does all the movements for BHM and their brand is on his truck. Its a very fancy carrier, a covered box van with a side door. I was totally impressed. Darren is a multi Morgan owner. Why 468? I asked...........It's obvious. Morgan 4 wheeler engines.

Now I wait. It's a new experience for me. I can't say that I like failing, but knowing your limits is also important.

You didn’t fail Dave. You’ve already accomplished a huge amount of mechanical work on your Morgan’s, far more than most of us on this forum, myself included……good luck in getting it fixed soon

Thanks Craig......

Fuel pump details










"Access"


When the frame crossmember is removed - just enough wiggle room.


And................

Dave you mention no fault codes or even the presence of an EML. I can understand the ECU being locked although you suggest it's been flashed then flashed back again. In any case it's inconceivable that OBD2 codes can't be read giving strong clues as a minimum to the root cause of your issue.

BTW I'm aware of low fuel pressure fuel sensor and high pressure fuel pump connections on GDI engine loom. I guess the latter could be some form of pump control but read it as electric fuel pump feed

They just don't connect Richard. I tried all mine. Son in Law has a laptop loaded with tech which works on most things but the GDI only responds to the Morgan Dealer package.

Unless it proves to be a random bad connection .... Will you get to the point where an aftermarket ecu might be the cheaper option! ? ... and the code access would be restored going forward.


K

I don't even know if an alternative ECU would work. You know how Morgan piece together bits from various places and make it work. It's beyond a random thing now, it's a thing! So it might take some figuring out without changing a lot of components. All I know is its not plugs or coil packs, and its not the fuel pump, or the fancy relay at the back.

That doesn't make sense to me Dave and likely illegal to deprive GDI owners of basic OBD2 fault information available on every other modern car on the road. Are you suggesting engine management lights (engine or spanner icon) don't appear either?

Note AI response to my query:

Completely blocking access to standard OBD2 fault codes is generally illegal in the UK and EU. Under Regulation (EU) 2018/858 (which continues to apply in the UK), carmakers must provide independent operators and owners with unrestricted, standardized, and non-discriminatory access to vehicle OBD and diagnostic information.However, many modern manufacturers now use Secure Gateways (SGW). While these firewalls do not block owners from reading basic diagnostic codes, they prevent third-party tools from clearing codes or writing data unless the user pays a subscription or registers for authorized access.The legality of these "secure gateway" blocks remains a complex, evolving legal battleground:European Court of Justice (ECJ): The court ruled in Case C-296/22 that manufacturers cannot impose restrictive conditions, such as forcing independent operators to use manufacturer-specific internet servers or registration systems to access OBD data. The court struck down manufacturer arguments that cybersecurity regulations (UN Regulation 155) justified limiting access for repairs.Emerging Regulations: Phased implementations (like the EU's extended Regulation 2026/699) are currently being rolled out to enforce fully standardized access protocols and prevent manufacturers from using cybersecurity as a loophole to control the repair market.Global Context: In the US, independent automotive groups and consumer advocates continue to lobby for broad legislation like the REPAIR Act, as digital locks and telematics data remain contentious

We tried mine too, 3 different brands and they wouldn't read either

Really sorry to hear your ingoing saga, could your GDI be going into some form of 'limp home' mode! Hopefully, Brands Hatch will be able to resolve the issues for you.If worse case scenario an aftermarket ecu maybe the better way forward, so they can get the engine setup just the way you want it, rather than reliant on a locked system.

One of the issues I'm becoming increasing aware of with some manufacturers is that updated/reflashs of the software can create problems with previously perfectly functioning sensors etc. problems that didn't exist pre the update/reflash. For example with Mercedes I try to avoid any software updates as they are well known to cause O2 and NOX sensors to malfunction shortly afterwards.Thats why I use a Mercedes independent engineer, who avoids updates where ever possible, because of the problems from experience he finds they can bring on older models, whether it's Mercedes increasing thru its updates, the built in obsolence of their older cars, who knows for certain.

RIchard, your posting on access to software was interesting. I thought that Euro 7 compliance requirements require a locked ecu, so that eg emission settings, safety systems cannot be tampered with. Of course it different scenario being able to read the codes as opposed to change the software.

Are you talking of a previous GDI you owned Jon?

Did you check the pump connector wires Dave?

They can fracture

I recall reading somewhere Rog a connector at the rear carrying white/purple fuel feed is under spec'd leading to high resistance at pins and connector melting. The matching wire one in your pic doesn't look too healthy.

The wires were sound as far as I could establish Rog. From memory the outer two are pump feed/earth, 7and the inner two for the level float.

Maybe it's illegal Richard but only dealers can access the fault codes. My engine light has never lit, except the one time I did a start with something disconnected, but an overnight with the battery disconnected reset the light

Jon came over to try his readers and none connected.

I understand your reasoning and share your frustration Dave at sending the car to BHM. Without fault reporting you are working blind and that for me would be intolerable on a modern DBW car. I'm also a little concerned that yourself and other GDI owners could be driving with an engine in potentially dangerous condition without any fault reporting!

No consolation but a new accelerator pedal sensor appears to have fixed my Roadsters random but increasingly regular severe throttle response issue causing misfire, which corrected itself every time with engine off for three minutes. There is a barely perceptible improvement of gentle power take up when driving in built up areas, when fault nearly always appeared. I'm guessing the twin potentiometers on old sensor had the equivalent of a scratchy volume control pot (however rare) as fault always triggered the same P2135 voltage correlation error code but with no freeze frame data recorded.

Yes, and unless MMC allow access, going forward there will be more GDI issues as the electrics age. Even assuming that parts remain available. I wonder if my problem is the accelerator pedal, time will tell.

The elephant in the room of course is the CX timebomb. A much more complex car. Morgan with a reputation for slow delivery of parts. And becoming very reliant on dealer attention. Combine this with aging electrics, and questionable availability of parts and you get a situation which I would not welcome.

I also think that if you have to sacrifice the AR flash to get through the MoT, it should be available again, either free, or discounted. Pigs might fly of course!

Well, it is about the only thing left!

My car has a completely different engine (GM Ecotec VVTi), a completely different ECU (MBE) and a completely different map from yours, but the only time I have ever had a problem with the car was shortly after the conversion was installed and the symptoms were exactly as you described:


The car would run ok but had no power, wouldn't pull anything over a tickover. Turned out that one of the new fuses fitted with the ECU and engine loom had blown from being under-specced, and it was the one protecting the fly-by-wire throttle circuit. My engine wasn't getting a valid throttle position signal so defaulted to a limp mode. Went from a 10A to a 15A fuse and I haven't had any further problem in the last 18 years.

If this turns out to be a fuse, I will be gutted!

Sometimes knowing 'too much' can cost a lot of money. Not long before I sold my MGV8, so early 2000s, I had a clicking starter. Not unheard of because the solenoid gets baked by the exhaust. I fitted a new solenoid, and no change. So it must be the starter motor. A new starter motor made no difference. Checked the cables and all OK, as I thought. So next was a new battery, or actually two x6v. No difference.

Now I'm struggling. Final throw of the dice, another check on the cable runs. The 6v batteries were under the back seat so an extra cable between the two but that wasn't the problem. The problem was a hairline crack in the battery positive terminal, which was a wrap around with one bolt through, and nipping that up, showed the crack. It cost a terminal to fix, but I paid for two batteries, a solenoid and a starter motor.

DAVE THIS REALLY IS A CONUNDRUM! You don't suppose AR locked your ecu to protect your/their download. The odd thing here is you can't access your OBD2 port. Going to be interesting to see exactly what is causing this though. Who reflashed your ECU back to standard? and how did they manage that. Did AR re chip your ECU in which case the reboot might have just confused things more. This surely has to be electronic as I'm sure you will have checked and checked the mechanical elements until you were sick of the sight of them. I do hope there is honesty relayed back to you and that a solution is achieved. This really flies in the face of what trad Morgans were all about. Slowly, slowly they have moved into this secretive market trying to make owners buy and service their cars with them, even effecting the few long established dealers available to us should we need them....... I do hope for their sake they have got the market right. The porsche owner will not put up with the one fully booked dealership nor the 400 mile round trip when they do agree to see him/her!!

For sure I know I would be exactly where you are now, without a clue as to where to look next. Think I'd be asking Dave, Monty the car, how to go about changing the whole brain and getting rid of that locked Morgan abomination.!

My absolute sympathy with your situation Dave and I hope MORGAN pick all this up especially as you have done so much to support Morgan and especially Morgan owners to be able to afford the ownership of their trad car. I always thought a FORD meant Afford!

As far as I know Sewin, all the GDIs are like this. The flash-back to standard was at the MoT at Ledgerwoods. The dealers can reinstall the standard profile because they were all sent a modified flash on the standard item, which I think dealt with the hair trigger throttle, which not all had anyway. Figure that out!
The AR flash can only be done at MMC and there was talk that this may be no longer provided soon. In addition there were two AR flashes. The full one if you have the AR manifold and system, and a lesser one if you have a non factory manifold and system upgrade.So there are four out there. Original standard, upgraded, AR half assed, and full AR.

Hi Dave, really sorry to hear of your problem. I'm with Richard I find it hard to believe that MMC have locked out basic OBD2 access. As I understand it OBD2 compliance was made a legal requirement in America for all new cars sold from 1996 and Europe followed suit in 2000.

My car is a 4/4 with a Ford 1.8 silver top Zetec. The car left the factory in November of 1999 and was fitted with an ECU that is not OBD2 compliant it doesn't even have a MIL light fitted. It just scraped in legally for this country by a couple of months. It could not have been legally exported to America at that time with that ECU fitted. It took me a very long time to find software and hardware that would connect to this car. I eventually did and it turned out to be Ford DCL protocol. By 2016 that should have been long gone.

I can't help but wonder whether the inability to connect problem, is in fact a wiring fault. I am sure Richard would be able to check if cables from the diagnostic connector share a common multipole connector with the MIL light somewhere on rout to the ECU. It may be the ECU connector itself needs reseating or even (most unlikely) the ECU is faulty. Even if MMC locked out OBD2 access there would be no point in disabling the MIL light and given your severe symptoms that should defiantly be illuminated.

The photo bellow shows the standard pin out for the OBD2 connector. The lower diagram is for your car, note the diagram does not mention that pin 16 is at battery + volts with ignition on or off. You can ignore the upper diagram that is for my car and ignore my scribblings.


Regards Tony

Hi Zach.

MMC and the dealer can access the port. Although I do wonder if the mapping is corrupted. The fault the second time emerged very slowly, over 20 miles, which is also weird.

Well hopefully it's getting the necessary identification, rectification and a permanent solution.

I remember when Mercedes first introduced ABS, I had a new convertible that every time it rained heavy it went into limp home mode, this was back in the days when there was no fault code memory, so unless you could replicate the fault with the engine running and a code reader attached , you stood no chance with intermittent faults.

Despite all of Mercedes vast experience, they never fixed it during my short ownership of the car Maybe a decade later, I was discussing the issue with a Mercedes mechanic, and he just had a wry smile, they eventually found out it was a faulty ABS sensor. As the number incidents of it's occurence increased across the range, they eventually found the root cause was a faulty batch of ABS sensors.

You may remember my 2012 Plus 4 sport lost all power. Everything was checked by Lifes fuses, connections all the onvious known areas to investigate and they couldn't find anything to explain why. An autoelectrian tracked it down to a burnt terminal/wire on the undersude of the fuse box, which was not obvious until you took the fuse box off........frustrating but fixable............thats why I always recommned a wiring check for anyone buying a used Morgan.

I can only image your frustration and sometimes sense of helplessness, as some things are beyond your control, but hopefully the fix whatever it is, will increase the knowledge base, if it is a generic fault,.of running a GDI Morgan, all you can do is keep the faith.............

.I don't allow the complexity of the CX to worry me, as I have neither the inclination or skills to work on it and accept the inevitable garage visits, and resulltant costs. hopefully infrequently...but it is a hand built Morgan.......and they can be more maintenance intensive, that other mass produced cars as a result........

In 2013, when I was adding over-riders to my 2012 P4, and MMC were building cars with over-riders, it took six weeks to get 4 over-riders and brackets from the factory by my dealer.

I've seen inside the hallowed stores complex and its brimming with stuff. I've seen the first box of assembeld parts which were the step 1 after the chassis of a Trad was first put on the trestles.

You would think that it would be a simple step from there to supplying spare parts, but it is not. This is Morgan.

This unfortunate saga is worrying and doesn’t reflect at all well on MMC.

What strikes me is the very different behavioural characteristics exhibited by certain models that to all intents and purposes should be very similar. Dave’s GDI had a hair trigger throttle from new whereas mine has never exhibited anything close to this, either before or after the ClubSport upgrade. Some early Mustang engined Roadsters exhibited the now infamous rev hang, yet this mysteriously disappeared on later models. My 4/4 Sport bordered on appalling, yet there are good folk on here who clearly love theirs. Perhaps I am trying to convince myself, and other GDI owners, that the particular issues with Dave's car will not necessarily be inflicted on all other similar models.

My admiration to Dave for persevering with this issue with metaphorically hands tied behind his back. Lesser mortals, including myself, would have thrown in the towel and summoned the dealer long ago. It must be unbelievably frustrating.

Curious as to why BHM? Geographically, there are nearer Morgan dealers to South Yorkshire.

I seem to remember he bought the car from them Chris & IMHO they are a good dealership

Morgan buys in all it's engines and gearboxes, so it is to a certain degree captive to the vagrances of the supplying manufacturer and the extent they allow modification to the ecu software without voiding their supplying warranty etc. Most engines ecu's tuned to operate in much heavier cars and so on. Weren't the ecu upgrades to the Supersport 400 undertaken by a BMW approved tuner, so they still exercise some control over the specification etc. of the engine. so protecting BMW's warranty and reputation exposure in using BMW engines etc in powering Morgan cars.

The original manufacturers may have made changes from the earlier spec'd engines to correct problems they may have experienced overtime in their cars, and it may not be anything that Morgan has done eg the Mustang engine rev hang. I note my autobox creeps forward more than I would expect so I have to hold it more on the brake when statutionary, which I think may be due to the lightness of the car compared to BMW cars and possibly the gearbox settings have not been changed (if they can be changed) to reflect the weight differential in applications.

So whilst it may reflect on MMC, some of these matters maybe completely outside of their control, or their freedom of movement to alter specification of supplied components.

Morgan, courtesy of engines available, have been dragged into the arena of overwhelming mechanical/electronic complexity where even the main dealers of world-level car manufacturers sometimes can't sort the problems of their own motors! ... not a great scenario going forward.

K

Dealers are like a box of chocolates. Some are better than others and what they do can vary considerably. Some have a reputation, which is not shared by all customers. But BHM is right up there. They have a wide knowledge base because they also look after race cars. I've known Keith, Sarah and Brett since I first met them at the Buxton Mog in 2009. I bought my 2012 75th Anniv there and my 2016 GDI.

Obviously there are closer dealers, in fact most are closer, and some are great dealers. But I chose BHM because of my experiences over the last seventeen years. I also did my book signing there in 2018/9 and will do another one in September/October this year. I could easily do other book signings at Dealers, but last time it never came up.

Anyway, from the above posts, you can see that the OBD plug should not be locked out, but that's exactly what Morgan did. Dealers only.

Hi Dave

Given the fact that your problem got worse gradually over a 20 min period I would think it is fair to say that it did not drop into limp mode, at least not initially. In my case with my Ford Fusion when there was a throttle position error detected the car went straight into limp. So perhaps in your case the throttle position sensing is not the problem.

On the subject of not being able to connect this intrigues me. I was in the exact same position when I first bought my present Morgan in that nothing I tried would connect but I knew that MMC and the dealers could. For a long time I came to the same conclusion as you that MMC had locked accesses to everything except their specialist diagnostic software. As it turned out after a lot of reading and searching this was not the case. What MMC had actually done is fitted an EEC that was long out of date and used a Ford only and now obsolete protocol known as Ford DCL which falls into the category of OBD1. I don't suppose you can blame them for getting rid of old stock on cars that were not destined for the USA where in 1999 when my car left the factory the car could not be sold legally. When you mention dealers and MMC can access the port there are in fact at least four ports wired to different pins on your diagnostic socket. These ports handle a range of different protocols and speeds I know of at least eleven variations. Even the very cheap and simple OBD2 readers will scan through all these ports and options on initial connection until they receive an intelligible response. I know all this dreary stuff from trying to work out why my car would not connect. Anyway I am confident that BHM will resolve your issue. I know that really this is none of my business but if it's not too much of a cheek I would love to know for my own education if they can confirm that all but the inner sanctum are locked out of these GDI cars.

Regards

Tony

The 400 is not an ecu upgrade; it has a different engine - a newer version of the B58 known as the “B58 01”, which has a higher output before you start tuning it. The tuning for 402bhp was done by BMW.

My understanding was as follows, we maybe at cross purposes here :-


'BMW approved the use of its engine and permitted Morgan to conduct its own throttle and powertrain tuning for the Supersport 400, provided Morgan utilized their official calibration partner, FEV''

Isn't that what I said, doesn't that not involve ECU upgrades/programming in conjunction with an approved BMW tuning partner. I didn't mention the engine type.......the point being that BMW still kept control over the process...... .

Whoops Just noticed my previous post should have read ECU not EEC

[Update from BHM......................................................................

Connected the laptop and no faults recorded.

Compared live readings with another GDI and all looked the same.

Tried your ecu on another GDI, and it ran fine so discounted ecu.

Uploaded all the info to the factory who wouldn`t look any further until the earth behind the brake servo was relocated on chassis. Made no difference.

Factory suggested trying the throttle body so changed that, and throttle pedal, but no change.

Tested the airflow meter from another GDI, (even though readings look good) and it now starts like a normal GDI.

Might put it through an MOT tomorrow with the donor airflow meter.


This is me now.......So, no faults recorded. So even with OBD access I would have been screwed at home. It doesn't really explain what's been going on with the MAF. I've cleaned it a couple of times since the first problem, but it never made any difference, so it was never high on my list. I suppose the learning point here is to start with the easy changes.

Dave,

If I'm reading your posting correctly the MAF is malfunctioning in some way, isn't there a serious of MAF error codes that would have been generated

Common error codes generated by a bad or dirty MAF sensor include:
P0100: MAF Circuit Malfunction
P0101: MAF Circuit Range/Performance Problem (often caused by a contaminated sensor or unmetered air leak)
P0102: MAF Circuit Low Input (e.g., sensor unplugged or shorted
)P0103: MAF Circuit High Input (e.g., faulty sensor reading maximum capacity)
P0113: Intake Air Temperature (IAT) Circuit High (The IAT is built into the MAF sensor on this engine)
P006A: MAP - Mass or Volume Air Flow Correlation (occurs when the MAF and MAP readings disagree)
P0171: System Too Lean (often triggered when a bad MAF sensor calculates less air than is actually entering, resulting in improper fuel mixture)

When these codes are thrown, the ECU will typically illuminate the Check Engine Light and may enter a "limp mode" to protect the engine until the issue is resolved.

Is it just a case you couldn't access those codes through the reader or the error codes weren't generated, from what you write it looks like the codes weren't generated? Will you be able to use a reader at home in the future or does that still represent a problem.

THe reason for the interest is basically when I was looking at getting the CX, I also came across a brand new GDI Works Edition which had been in storage from new, which had the 180 bhp ecu and exhaust system, similar or the same as your car. It was your ongoing experiences and issues that put me off getting the WE as well, so I've followed your progress with interest on this particular issue, more to vindicate my decision not to get the Works Edition.

There were no error codes John, and I don't expect to be able to access the error codes when I get it back. I just get the feeling that this is how it is with the GDI.

So even if I had been able to access at home it would have told me nothing. It was basically the last thing BHM looked at because the computer was showing identical parameters to a GDI running correctly.

Not good, I can only imagine your frustration, but also relief to be getting your car back MOT'd.

Glad you have got the car back and BHM have done what they excel at.

Two observations I have never owned a code reader as over 43 years I have not seen the need as faults thus far for me have been logic deduction, now I'm happy to admit I may have been lucky.

The other is that after a lifetime of fault finding and rectification for a living in the commercial electronics field and found on occasion too much information can steer you away from the initial cause, it is a very fine line.

I think your explanation and process will be a great help to others with a GDI though.

I run my cars most days excepting salty conditions and I think regular running makes a huge difference to the wellbeing of the cars and me observed over 43 years and not a battery charger in sight....

Could the MAF have a hairline fracture that's giving flaky feed to the ECU when running (vibration) but static test the code reader sees it as ok ?

It could be that Jon. Certainly fuses can play with hairline cracks, and cause erratic faults, but usually a fault logs and pings the EML. Whether the GDI has a limp home remains unknown.

At least we now have a symptom, and cause. This second occurance recently though, was very gradual over distance, and only maxed out when we got home. After that it was constant. MAF cleaner had no effect, so perhaps a hairline opened up slowly. At home you just don't have the capability to substitute everything one at a time, to eliminate and close in on the cause.

At least I have a new fuel pump, and had the 'pleasure' of fitting that!

A few years back I was in Scotland with a pal and his +8 was refusing to behave itself. Called out the AA and the mechanic immediately removed and cleaned the MAF assembly and its connectors without even bothering to hook up a diagnostic.

He reckoned that the overwhelming majority of faults he encountered were MAF related so it was always his first port of call. He was right, the +8 immediately burbled into life and the hoon continued.

This is AI's search re MAF, AI also states that the Morgan GDI engine does have limp home mode (for what its worth) I can't imagine a vehicle not having a limp home mode these days to protect the engine. Does only your GDI not give you access to a reader, or are all GDI's in effect locked out. The reader element I left in, just in case others can read their error messages.


A Mass Air Flow (MAF) sensor might not generate Diagnostic Trouble Codes (DTCs) if it reports plausible-but-inaccurate data, has minor electrical or circuit faults, or is gradually degrading and the Engine Control Unit (ECU) is still compensating for its flawed readings.

Common Causes of MAF Sensors Not Generating CodesSensor Degradation:

The MAF element degrades slowly over time due to dirt, oil, or age. It sends incorrect air volume readings to the ECU, but because the signal is within the sensor's normal voltage range, no code is triggered.

Contamination: Oil residue from reusable performance air filters, road dust, and exhaust fumes can coat the delicate hot-wire sensor. It will misread the incoming air without tripping an open-circuit or high/low voltage code.

Air Leaks & Unmetered Air: Unmeasured air entering the engine after the MAF sensor (e.g., from cracked intake boots, failed PCV valves, or loose vacuum hoses) causes the engine to run lean. The MAF functions correctly, but the resulting O2 sensor or misfire codes will mask the underlying leak.

ECU Compensation: The ECU can adjust short-term and long-term fuel trims to compensate for a slightly failing MAF sensor. It artificially keeps the engine running smoothly, preventing an immediate Check Engine Light.Wiring & Connector Issues:

Corroded terminals, high resistance, or a loose harness can cause power drops or erratic signal spikes. If these issues do not cross the threshold into a permanent open or short circuit, the ECU will not log a code.

How to Diagnose a 'Silent' MAF IssueIf your vehicle is experiencing symptoms like poor fuel economy, rough idle, hesitation, or sluggish acceleration but lacks error codes, the issue can often be pinpointed using a live data scanner.Monitor Live Data: Connect an OBD-II scanner and read the "MAF in grams per second (g/s)"

. A general guideline is that a warm engine at idle should show a g/s reading roughly equal to the engine's displacement in liters (e.g., a 2.0L engine should read around 2.0 g/s).Inspect & Clean the Sensor: If the readings fluctuate wildly or are stuck at zero, inspect the wiring or carefully clean the sensor wires using only CRC Mass Air Flow Sensor Cleaner.

Never touch the delicate filament.Check for Unmetered Air: Use a smoke machine or inspect the entire intake tract between the MAF and the throttle body for cracks, loose clamps, and leaking vacuum lines.

Hi Dave
Great news on getting your car back up and running I am pleased for you. Like you I am an old distributor and carburettor man and used to fixing my own car so know how frustrating it is to have to hand it to someone else. But, as you say you can at least take comfort in knowing that without the resources available to BHM you would have ended up there anyway.

When I got my present Morgan I decided I would try and learn something about how this computer control stuff works and how to fault find with it. I found a book called “Automotive Diagnostic systems” written by Keith McCord. This is very informative and together with this, and bits and pieces on the internet got a better understanding of what goes on. The following is a bit of a simplification but basically as I understand it the computer has to deal with two things. (1) inject the right amount of fuel to get the correct mixture for different engine loads and RPM's, thus replacing the carburettor, (2 ) set the correct ignition timing thus replacing the distributor. It does this with a combination of referring to tables stored in its memory that we refer to as the engine map and measuring engine parameters with sensors.

In the case of the fuel mixture it starts by injecting the amount of fuel for a given rpm and engine load that is stored in the table but it has the ability to trim this value by as much as 25% in either direction leaner or richer. If it attempts to trim outside this range it will throw up an error code saying trim out of range and in what direction.

So with my basic understanding I have been trying to think up a story that would fit the facts in the problem that occurred in your case.

For what its worth here it is.

First there were no error codes and that must mean all the sensor values the computer was receiving must have been within their accepted ranges even if they were wrong.

John said that your MAF also contains the intake air temperature sensor or IAT so when the MAF was changed so was the IAT. The purpose of the MAF is to measure the weight or mass of the air entering the engine but what the computer really needs to know when trimming the fuel is the weight or mass of the oxygen contained within that air mass. That will vary with air density the hotter the air the less dens and the less oxygen. To calculate the density the computer needs to know the intake air temperature. Suppose your IAT was within range but was reading higher than it should,. that would be interpreted as the air being less dens than it actually is and cause the fuel trimming to reduce the amount of fuel injected and you would be running too lean. Also the hotter the air the hotter the engine and to protect against detonation the computer will retard the ignition. As you drive along the engine bay will of course get hotter and this will increase the intake air temperature making the situation even worse this is in keeping with what you experienced. Under these conditions you would be running too lean and with ignition too far retarded and no error codes because every thing was in range. Remember this is my fairy story with absolutely no experience of chasing these faults but based on what I have read but may have miss interpreted.

I am still trying to learn more about this subject so if anybody reading this can find holes in it I would love to hear.

By the way, following the progress of Monty and his deep breath on this forum I have found it to be quite educational in regards to engine mapping and computer control. Thank you Montegue.



Sorry about the long post


Regards Tony

In answer to are all GDIs locked out the answer is no. I had one of the first GDIs from new, a 2014 car, that used to regularly display the engine warning light when applying full throttle after a lengthy time at low revs. So stuck in traffic and finally having an overtaking opportunity I could almost guarantee the light would appear. I used to carry an OBD reader with me so I could clear it when I stopped. No idea if Morgan locked later cars.

Here are some stats.

First MOT in June 2019:
2500/3000rpm.
CO%vol 0.10 Max 0.20
HCppm 11 Max 200
Idle
CO%vol 0.285 Max 0.30
Lambda 0.998 Range 0.97 - 1.03

2025 MOT
Failed AR flash
2500/3000rpm.
CO%vol 0.516 Max 0.20
HCppm 441 Max 200
Idle
CO%vol 0.03 Max 0.30
Lambda 0.994 Range 0.97 - 1.03

2025 MOT
Pass with standard map
2500/3000rpm.
CO%vol 0.019 Max 0.20
HCppm 9 Max 200
Idle
CO%vol 0.264 Max 0.30
Lambda 1.003 Range 0.97 - 1.03

New MOT. New MAF:
2500/3000rpm.
CO%vol 0.07 Max 0.20
HCppm 25 Max 200
Idle
CO%vol 0.17 Max 0.30
Lambda 1.000 Range 0.97 - 1.03

Dave just out of interest I see your tester is using a generic limit for the lambda.

Page 126 of the 18th edition



Not trying to be a smart Alec, but mine is always tight on the lambda with a k&n filter fitted. I take a copy of the emission book with me, just in case.

I'm not trying to be funny here but if the scanner even if not locked out couldn't find a fault code what does the EML element record? My past history with modern cars has shown me that the MAF faults are the first to register even slightly out of normal function parameters even if still within range. Your car was clearly way outside of this and was this way from new yet Morgan were unable to find it. Even BHM clearly couldn't find a fault when scanning your EMS this time and I'd guess they had viewed live scanning as well..... if they can? I think that your history of your journey trying to solve this problem allowed BHM to finally follow an accelerated fault path of known issues with the Gdi and led them reasonably quickly to the MAF sensor, so well done Dave you had a very relevant part in this diagnosis too!

Now my engine is the original Duratec and I'm not locked out of the OBD2 port but what you can interrogate quite frankly is next to worthless so I guess I wouldn't have been able to have done any better than you on the Gdi. I'm sure I would have covered the same checks on the MAF system, mechanically and electrically as you did and struck it off the list of potential faults....... looks like we may need to hold a known master set of components in order to carry out our future checks. Lastly, I can't see why Morgan would lock access to the OBD2 port. Firstly its illegal, and I cannot believe that after all this time a bypass solution wouldn't have leaked out, BMW can't keep people from accessing their systems for very long yet the Gdi has been around for 12 years! If my plus 4 is anything to go by I think the OBD2 port has little to offer in the way of diagnosis. Still it has done one thing Dave......... I'm sure we will all look far more closely at the MAF in future and I'd probably group the throttle position sensor in that as well!

I've used that list for my Roadster IcePack, but it doesn't list the GDI, so I take from that that the generic is the relevant range.

Sewin you nailed it. BHM have never encountered this problem and so in the future, will look at the MAF sooner. I certainly will, and if this now happens to any other GDI, they have a head start, because it might just be that changing the MAF resolves it immediately.

Hindsight eh? If only I'd known.

Yes indeed Dave! shame its your wallet that's paying BHM to become the experts though. I really am starting to wonder just exactly what is accessible via the OBD2 port. As I said little is available to me on my Duratec 2010 car. yes you can clear fault codes but so can the most rudimentary readers. and any fault codes I have had which have been almost negligible I have induced myself from disconnects or component changes. When I first got the car the OBD2 port was nowhere to be seen, I eventually found it tucked way up out of the way and unless I hadn't removed the dash it was ..... er! Hidden? I wonder if Morgan had just removed the power lead connection from the block on these locked cars.
Anyway Dave, I think you probably were closer than you think to solving this one. Had you had someone like RichardV6 looking at the car together with you I'll bet you would have found it.

Good news it's sorted Dave, I assume a spare MAF will be added to the Scottish tours kit

Out of interest, did you ask BHM if they could unlock the OBD2 port for your own future access ?

That is not a question for an open Forum maybe Jon

I didn't ask. Given that there were no fault codes when it failed the MOT with the AR upgrade, where both CO and HC was more than double the maximum limit, I really don't see the point. It's almost as if the ECU is blind to faults, and just alters fuel pressure as a consequence of the MAF input. It will remain a paradox.

It's tempting to get a spare MAF, but it's such a rare occurence. I had the Roadster run a bit unevenly a few years ago, and a squirt of MAF cleaner sorted it. That's the usual routine. This is another reason why I don't really worship oiled filters like K&N, because there's a risk of oil droplets contaminating the MAF sensor.

I picked one up a few years ago but have never fitted it. They aren't expensive but my reasoning was that with a 2007 engine they might become unavailable in the future. Even now they are only around £90 on eBay.

Yesterday I did decide to have a look at mine and gave it a good squirt of sensor cleaner. I do have an oiled K&N filter but I rarely re-oil it and have never had a problem with contamination.

Ditto re the K&N slab filter on my Roadster. Cleaned MAF sensor twice now always catching the drips of dedicated cleaner onto white tissue. Absolutely clear though as was our Mini's. I guess there is an opportunity to over oil the element but the instructions clearly say just enough of the red oil to show as a uniform covering on the filter material after washing it.

I don't suppose you can remember the fault code Andrew . At a guess maybe O2 sensor 1 although engine would be in open loop under such conditions.

Slight thread drift.... Sorry Dave... As I have previously mentioned I do follow a young lady on You Tube as she m/cycles solo around the world, and into all sorts of road and off road conditions from jungles to deserts and everything in between..... For her current escapade through the Stans, China, and across Mongolia, deserts and all, she chose to ditch modern tec and went back to a pre digital Yamaha in the hope of increased reliability by way of fewer things to go wrong....which overall seems to have worked out rather well, if interested you might like to beam up Itchy boots to get an idea of what she is about...?

So we are all seeking our MAF sensor now, just in case…but it looks like the standard 2.0 Duratec engine that preceded the GDI does not use a MAF but instead has a MAP sensor down on the inlet manifold. This measures pressure and though not quite so accurate as a MAF, requires virtually no maintenance.

If that early GDI was throwing an EML at the drop of a hat, that does suggest that MMC 'fixed' it.

The EML only came on after the manifold and cat was changed for a less restrictive system. Sorted the hole in the torque curve between 2000 and 2500 revs but the free flowing cat, presumably, didn’t always get on with something in the settings. I haven’t heard of anyone commenting about low rev torque issues on later GDIs so perhaps Morgan did change something.

I only read the first long report. But last year I had a problem with "non starting". A few things changed and tested. A demand "fuel-ECU". But I also changed one coil pack in cause the "safety nose" was gone. In cause I´m in Germany and BOSCH is always available a BOSCH.

But there was something wrong. A look with my OBD-Reader: nothing. So I went to the friendly guys from our TÜV-Station for a high quality check. (for a bargain of 5,-EUR for a coffee). Nothing. But than the manager said: sounds a little like misfire. So back home and changing the BOSCH back to the FORD coil pack. Problem solved.

With a deeper look I noticed: when the BOSCH is fitted und unscrewed you can put little pressure at it and it gets a little deeper in the hole. The FORD sits tight.

So have a look, and when you're not on the save side change back to FORD coil packs.

have a look here: https://www.talkmorgan.com/ubbthrea...lpful-part-numbers-2018-plus4#Post827585

Greets René

I'm really pleased to hear that with the help of BHM Dave got to the bottom of his issue, owning what amounts to a £35k paperweight is every car owner's nightmare. Direct Injection can present many challenging issues to diagnose, this moves to virtually impossible if you're then locked out of the ECU. However, it sounds like even with the dealer software no fault codes were throw, so BHM were forced to resort to the highly flawed diagnostic method of 'Parts Darts'.

Despite a happy ending to the saga, it does sound like the situation was what one might justifiably describe as 'highly unsatisfactory'!



The excellent and easily tunable port injection Duratec engine in the pre-GDI Plus 4 runs a pretty basic engine management system controlled by a Ford 'Visteon' ECU, as found on a Mk3 Mondeo. For example, while the injection is fully sequential, it still runs good old wasted spark ignition and a robust proven MAP sensor from Bosch. TBH it's late 90's engine management technology, however, in my humble opinion there's absolutely nothing wrong with that, because by the late 90's engine management had really been fully perfected.

When I studied the Visteon, the only element that surprised me was that it runs rather old school narrow band lambda sensors which are more 80's than late 90's engine management technology, my guess is Ford were saving money as wide band lambda sensors were quite expensive in the late 90's when the Visten was conceived. When you look at the Visteon specification it's quite obvious Ford's design brief was to create a robust cost effective engine management system that put proven technology ahead of the latest ideas available at the time. The new technology was more costly and still not fully proven, which is why it got good old wasted spark instead of fully sequential coil on plug ignition, and basic narrow band lambda sensing rather than wide band.

Critical engine load sensing is by virtue of a tried and trusted Bosch Manifold Absolute Pressure (MAP) sensor, and an equally robust crank position sensor from Bosch to give engine speed, both manifold depression and engine speed are needed when using the 'Speed Density' method of calculating engine load. For the record, when measuring engine load that's so critical for fuel trims, what you're actually trying to measure is the amount of air entering the engine. It seems counterintuitive, but air has mass, and because a Mass Air Flow Meter (MAF) sensor measures the true mass of air entering the engine rather than using manifold depression and engine speed to calculate it, a MAF is always the superior engine load sensor solution.

However, it's a bit like the difference between good old wasted spark and fully sequential Coil On Plug (COP) ignition, COP is unquestionably more efficient, but you've now got four individual pencil coils shoved directly down the plug wells, and as we all know the one thing ignition coils hate most is heat. For all these reasons, and when tuning Monty, if I could have retained the good old Visteon ECU with its simple but effective wasted spark ignition and MAP sensor, I would have done exactly that.

Don't get me wrong it's hardly the last word in engine management tech, far from it, but it does leverage the clear reliability advantages of sensor and operating systems that are super proven to be insanely robust. Indeed, you could easily argue the Visteon represents a perfect example of that sweet spot moment in engine management development when efficiency met outstanding reliability, and before things started to become excessively complex.

The truth is, if we didn't have ever stricter emissions targets to hit, with the exception of improvements in lambda sensor tech (wide band), engine management technology could have happily stopped with port injection controlled by systems no more complex than the likes of the good old Visteon

For what it's worth, I only replaced my Visteon ECU because I'd pushed it outside of it's operating range, sadly accessing the fuel and spark tables and making the necessary minor changes required, proved impracticable at the time. However, as I understand it, this situation has now been overcome by Williams Morgan. Revealingly, despite my EMU Black giving me the option to push the engine management technology to the next level with features like fully sequential COP ignition, l actually elected to retain the good old wasted spark system for it's bulletproof reliability. This is now proven to have been the right decision as Monty happily spins to 8,300rpm with zero ignition breakdown at these heady engine speeds, thus proving the simple Ford wasted spark coil pack is refreshing without any issues at all.

Equally, the perfectly functional and robust MAP sensor was retained, so with all the existing sensors, coil triggering and even the idle air control valve retained the existing factory loom could be utilised with no modification at all, this is what's referred to as a 'Plug & Play' installation. Beyond one simple additional standalone circuit for the new wide band lambda sensor upgrade, and the USB cable for comms between my laptop and the excellent EMU Black ECU, it's all the original loom.

With the existing engine management wiring remaining unaltered, this 'Plug & Play' approach eliminates 95% of the headaches than can come with an aftermarket ECU installation, at the same time it also removes the cost and complexity of building and laying a new loom. In simple terms, essentially what I've ended up with is a slightly enhanced and fully tunable Visteon

In terms of technology enhancements, all I actually elected to add was wide band lambda sensing, the original rather ancient narrow band sensors can only measure accurately at stoich (14.7:1), so a wide band lambda sensor becomes a bit of a no-brainer. When paired with my EMU Black it allows precise measurement from 0.68 Lambda up to 1.36 Lambda (approx. 10.0:1 to 20.0:1 AFR). With the release of the highly robust Bosch LSU 4.9 WBLS, that paired with the lightning fast processor inside my EMU Black Monty benefits from delivering a response time under 100 milliseconds, it would have been madness not to upgrade to wide band!

However, because my priority is reliability over pushing at the bleeding edges of engine management tech, I've retained the Bosch MAP sensor and wasted spark arrangement. For anyone with a standard port injected Duratec Plus 4, that to me represents the traditional chassis Morgan sweet spot combining a highly efficient and reliable modern twin cam engine with a simple yet effective and robust engine management system, the good old Visteon ECU you already own is more than up to the job. And even if you are doing some mild tuning, which can easily bring you close to 180hp, the Visteon will still cover your needs with a proven and cost effective re-flash from Williams Morgan.

In summary, and at the risk of being accused of thread drift, these days you really only need a 'Plug & Play' EMU Black if you're planning to go beyond 180hp, or if you're an incurable Geek like me