Talk Morgan Forums Morgan Sports Cars Morgan Three Wheeler & Super 3 Bad Idling, Bad Starting, EML, Error P0505

Evening Folks,

Having successfully had the car MoT'd last week (a subject for another post in due course...), I was looking forward to getting out and about in the tricycle as the weather warms. But when I tried to start the (still warm) engine to put it back into the garage, it took an age to start. Much chuffing, popping and coughing, but eventually it started. Seemed to run on a single pot for a while, so took it out for a drive. Drove OK, albeit with more back-firing on over-run than usual. Still wouldn't idle though.

Took it out yesterday and although it started OK, idle was still rough as hell and the EML came on. Had a look with Protune and it's thrown a P0505 error - "Stepper Motor Malfunction". All seems to tie up with the symptoms, so I guess it's one of those errors that really is the cause, not simply a consequencial error due to something else.

So took it into local dealer today and idle is now at 2500rpm, so clearly that Idle Control Valve is knackered. Spoke to Matt in Wales and unfortunately I just missed an order of parts from the US which could have had me a new one next week. Hopefully Bell & Colvill or MMC have one around somewhere.

Anyone else come across this one or am I a pioneering first timer for a P0505?!

Sounds similar to a problem we had on a Shogun Pinin. The throttle valve controlled by a stepper motor had partially seized to the point it was intermittently jamming in a certain position, hence unable to respond to ECU commands. Symptoms were high idle speed then little or no power as clutch let in.

New one was £350 + VAT exchange BTW!

According to our friendly Welsh expert, a new ICV is only about £80 on his price list, but Lord knows what it might be from MMC. Let's see what dealer says and if necessary I may have to get one direct from the US, assuming of course that it's that simple a fix...

is your battery good or has it been disconnected.? My Elise did that after the battery had been disconnected and I needed to simply reset it. You can also pop it off and clean it with Carby cleaner to see if that helps.

The below advice is lifted from the SELOC wiki for the S2 Elise and is probably applicable to a lot of modern IAC devices. A few turns of the key to on then off, allowing the IAC to rattle its way back each time and it was done.

"S2 (PWM) The S2 ECU cant measure where the IACV is so has to count the drive pulses it sends and remember the poistion, then tries to return to a datum every ignition on/off. If it loses track e.g. battery disconnected the ignition needs to be switched on to position 2 and off several times to run the valve back to the datum"

If that all works just clear, or have someone clear the code from the system.

Although I hadn't disconnected the battery (and indeed it's always on an optimizer, so always nice and full), maybe I should have tried this trick before taking the car to the garage. I had to do this on a previous car project and I understand the theory. That this ICV suddenly died is a little suspicious, but hopefully a simple replacement will get me back on the road. Thanks for the input.

So, following further diagnosis by local dealer B&C, it seems that they have issued last rites to both the Stepper Motor AND the ECU. Quite why both should go bad, but having swapped ICV and ECU from their demo car, mine would only run properly with both components from the known 'good' car. So I now need another ECU as well as an ICV.....

....so I am going to look into getting a programmable S&S VFI unit and try to get this mapped for the car. I am very aware that the cars don't even start with one of these 'open' units, but someone, somewhere must have an idea as to what the fix is? I will speak to Matt in Wales again and see what he thinks. If I do end up dragging the card to him, I might as well go whole hog and get me those Roller Rockers too, which I know someone fitted, but can't remember whom - was it nippymog?

Ideally I end up with an ECU mapped to my own mods, which of course is what every proper setup should include.

I'm not sure I have the fight in me to argue for a MMC contribution for early failure, but should an ECU really die in less than 3 years and on a car with only 7500 miles on it?!?! Gotta love these tricycles eh...?!

Maybe worth a call to Garage56?

https://garage56.co.uk/product/m3w-mappable-ecu/

Also I'd raise it with MMC before doing anything else - I assume it's not long out of warranty so they may make you a decent offer.

I'd spotted that and am on the case already - good old G56! I will also call MMC today and see what they think of things.

The SEARCH facility on TM is pretty dire and despite trying to look for references to ECU, it tells me none exist. However, I am sure there are quite a few of us who have had ECU failures, but I'm not sure if any occurred outside of warranty?

Here is one thread on failed ECU, I searched for "management"


http://www.talkmorgan.com/ubbthreads.php...saga#Post314557

Thanks Rog - I don't feel quite so alone now!