Uneven running of engine

[mikecg]

Hi, After 5 years my M100 car has developed its first problem. It starts but has an uneven tick over, it also miss fires at every press of the accelerator which after a few seconds disappears and at the chosen revs it runs smoothly until I increase the throttle further. It does this up to maximum revs and always seems to clear a few seconds after each increased accelerator depression. There does not appear to be any loss of power other than during the missfire.There are no error codes showing, I have added some fresh premium petrol in case the little that was in the tank had some contamination.
Where do I go from here?

[FunElan]

Sounds like you should try HT leads, coilpacks, and possibly a cam angle sensor? When I think 'misfire' those are the 3 things I'd look at

[Rambo]

So no CEL illuminating ? And no error codes stored ? I take it you don't have access to Elanscan ?

Do you know which cylinder you get a missfire from ? You can easily check this and the simple things first ie plugs, leads and the coil packs.

Has your car been laid up for a lengthy period ? A few M100 owners have also experienced problems recently with sticky injectors, usually after a lengthy period of non use. Probably attributable to cheap fuel, lack of injector cleaners etc....

See here for sound advice ........ viewtopic.php?f=38&t=28729&p=367483#p367483

Once you've diagnosed and sorted out your problem(s) it might also be worth checking the timing (in service mode) and resetting if required (16° BTDC)

[mikecg]

No stored codes, am going to build an elanscan cable to help with the diagnosis . The car is only stored over the winter months and was running ok after its first few runs in April May. But will check all as suggested and report back.

[mikecg]

Right, first test was as suggested to listen to the clicks from the injectors, I have a remote controlled battery isolator so can turn the on the ignition key permanently and switch the battery on and off . Thought i had heard only three clicks, so removed wire clips to help determine which injector is not working and removed all the injector connectors but still hear three clicks from within the engine compartment which are obviously not the injectors?

The car will start, so how noisy is this injector click and is there a way of hearing it better? I have tried a screwdriver against the body and my ear but get nothing.

[Simon_P]

Injectors - Put one end of a long rod or screwdriver onto what ever you want to listen to and your thumb then ear onto the other end.

HT - in any gear running smoothly - depress the accelerator until it missfires, if you ease off slightly and the missfire stops and can play the throttle to make it missfire it is likley HT, usually coils, sometimes plugs.

[mikecg]

Right problem solved. Nothing to do with the injectors. One of the original coil packs was faulty, new one acquired and car running as sweet as a nut.