bmw missfire - dominic clegg
model:BMW 318 IS COUPE 1997
FAULT:WHEN CAR STARTED FROM COLD VEHICLE SOUNDS ROUGH POSSIBLE MISFIRE.
WHEN WARMED UP AND IDLING ENGINE SEEMS TO NOT TICK OVER SMOOTHLY.


ANY POSSIBLE SOLUTIONS (ALREADY REPLACED SPARK PLUGS)


THANKS D CLEGG
Re: bmw missfire - Mike Harvey
Dominic,
Whilst I'm not familiar with this particular engine, it could be dozens of things.
Could well be an injector fault. Temperature sensor out of range. Has it a distributor cap? If so they are often not cleaned out on service with electronic ignition, and can track internally if dirty or damp. Could be cracked also. If it has individual coils, one of those or the plug cap could be faulty, or HT lead. (Try looking under the bonnet when it's dark and looking for signs of tracking- blue sparks somewhere). Lambda sensors can cause all sorts of faults like this. If you can get it out, try cleaning it with carb cleaner. Whatever it is, get it sorted pdq before your cat gets kna****ed. It would help if you could get a fault code from the ecu to narrow the search. I'll have a look when I get to work tomorrow to see if you can get the codes to flash up on the BMW without a reader and let you know, though my bet is one of the other experts will sort you out first!
Good luck
regards
Mike
Re: bmw missfire - Andrew Moorey (Tune-Up Ltd)
Quite likely to be ignition coils. Was there any improvement, briefly, when yo replaced the plugs? If so possibly the spark plug insulated boot may have failed. Look on the old plugs for a tell-tale dark line running over the surface of the insulator. The other probability is an air leak at the inlet manifold gasket, the brake servo hose or other small bore vac hoses.
Good luck,
ACM
BMW misfire - David Lacey
We seem to have lots of problems with all sorts of vehicles with their Ignition leads failing. Rover, VW, SEAT, Vauxhall to name just a few that have an appetite for HT leads.
I'm not sure if your car has HT leads, it might have Direct Coil Ignition - if it does, best take it to a BMW specialist (not dealer!!) for diagnosis
Rgds
David