Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Gems +8 cutting out

My 2002 Gems +8 is cutting out, it does not happens on all journeys, but on most of them, and within 10 minutes or so of journey start. When it happens it loses power for 5 to 10 seconds and then cuts out. The oddity is that it will start again quite happily on the second pull.

I cannot duplicate the issue at home by running at 3000 rpm until all liquids are hot, and when I took it to my usual Garage they also could not duplicate the issue.

There is a back story, I had not used the car for about 5 months and took to the Garage (which I have been using for about 30 years) for a full service with all liquids changed and some electrics:- wiring up a Magcode connector and fitting a Victron smart shunt - the reasoning for this may be worth another post. The Garage also reported that the petrol had gone bad! 12 months old E10.

On picking up the car it died twice on the way back, I brimmed the tank with fresh fuel (and petrol conditioner) and rather hoped that time and usage would fix the problem, but alas not.

I am now at the stage where I need to start playing parts and/or servicing bingo, so I was hoping for some suggestions that I could take to my Garage, I will also ask them to temporarily disconnect the smart shunt and Mag Code connector although I am reasonably sure that they are not part of the issue.

The MAF is one area I guess, but I would think that could be responsible for poor running rather than a no-go situation? The Fuel Filter was replaced at the service, and there is no "sucking" when I open the fuel cap after it has conked out.

So all suggestions are welcome.

Commiserations as these intermittent faults are the worst type, not familiar with the Gems system but I have heard of very similar symptoms being cured by renewing the ignition amplifier situated adjacent the coil itself on my 3.9.

Good luck.

Two thoughts

Does the GEMS system have the same idle stepper motor as the 14CUX? That was the cause of mine cutting out and a decent replacement cured it

As for the ignition amplifier, I changed that with no impact. Not sure if I still have the old one but you are welcome to it if I have. I’ll check later if you like?

Not being funny here Rovert but I guess the car drove to the garage alright with no problems even on old fuel? How about removing the victron smart shunt and the magcode connector and trying it out then. Where have you installed the mag connector, what power systems does it switch? I know that the smart shunt is just a blue tooth battery state indicator but could that cause a problem somewhere.

Forgot to say, if you disconnect the electrics to the MAF the car will run as it will go into failsafe running and the engine warning light will come on, might have to clear a fault code after.

Have a look in gomog. In the Plus8 specific section. There is also a link to the Gems manual in there.
Is your MIL light coming on at all?
Do a diagnostic check using an OBD tester.
I had a 2002 Plus8 with Gems. I have an Autel Maxiscan that is a good tool. By using the gomog links and Maxiscan I sorted a couple of issues.
First was MIL light intermittent. Maxiscan diagnosed an " intermittent random misfire". Checked everything but what sorted it was moving to V-Power petrol. It only came back when reverting to 95 octane petrol. I then alternated fuel to reduce the prevalence of 95 octane.
Second MIL light trigger was for an oxygen sensor problem. Identified as a post cat sensor heater problem. As it was post cat no effect on engine running. New sensor found using the Gems manual and Maxiscan to pinpoint and confirm the sensor that failed, and part numbers found in the manual and ordered from Rimmer Bros.
A diagnostic check is a preferred first step as it might narrow down the issue and save random component changes as there are several that might be the cause. Any faults found by the Gems will be kept so the OBD tester would ( should) find them.

Thanks for all the help Gentleman

Richard, I am not sure if the GEMS has an ignition Amplifier (?) if it does i am embarrassed to say that I have no idea where it is.

Grumpy, The stepper motor on the GEMS controls the IACV any problems as far as I understand it would typically be associated with idle problems but I will add that on my list to the garage to check out

Sewin, Yes I will get the garage to disconnect the shunt and the Magcode connector when I take it up, It is straight forward to do but I need to get under the car to do it which I cannot do at the moment. The Magcode is just used to connect the CTEK battery conditioner to the battery.

Sospan, Yes Davids Poole's Gems manual (as proof read by our very own Luddite) is a very useful thing. I do not have an OBD tester but it is something I think I will need to invest in, so thanks for the heads up on the Autel maxiscan, may I ask what what model number is it? No MIL light is on, and embarrassingly I did not ask if they did an OBD check last time it was at the Garage which really was the first thing I should have asked, Next visit I will ensure that they do, They have some pretty decent kit which can emulate the Rovacom system which picks up more stuff than a standard OBD reader.

Brian if it has one it is mounted on a small alloy bracket on the inner wing close to the coil and one shot oiler I'll get a picture of mine in a bit.
They are known to break down under high temperature and seemingly recover when the temp drops.
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Excuse the muck under there I use her as often as the weather allows and down here in the sticks the farmers leave a lot of tyre-field shedding which gets everywhere.

Thanks for taking the time to post that Richard,

If there is one thing that's benefitting me on this exercise it is learning more about the GEMS RV8 which I now find uses a coil pack rather than a single coil.

You are welcome Brian, like I say I know nothing about the Gems system, so I've learnt something new too which is always good.