Author Topic: Missfir on cold start problem. Help (Read 3155 times)

bbarnumboy · « **on:** March 24, 2009, 07:36:07 PM »

hi guys i have a 1993 318is. my m42 is having a problem where, it will only run on 3 cylinders for about 20 seconds after startup, and then the 4th one kicks in. i can hold the revs up to about 2,000 rpm and wait and once that last cylinder fires up it revs and is good to go.

i thought it could be plugs so i replaced them. after taking them out i noticed all were fairly white, more on the lean side. but one, "iam not sure of the cylinder numbers on this engine" plug farthest fwd of the car was black, as though it is running quite rich.

the car will excessively condensate, like exhaust does on a cold day. it does this till fully warmed up for a while, almost like it is smoking horribly but it is not smoke, just very thick condesated exhaust, and it is so thick it will trail heavy behind me, and slowly go away, but i am 90% sure it is not smoke.

to get a better idea i replaced the plugs and the engine was bone cold and amazingly it fired right up on all 4 cyl. about a day later it started the issue again, and i think that one plug may be fouled out again.

sorry to go on and on, but any ideas as to what my problems could be? it is embarassing down the road and a hassel on startup. it is straining my starter alot trying to turn this engine,

bbarnumboy · « **Reply #1 on:** March 25, 2009, 07:31:06 PM »

colin86325 · « **Reply #2 on:** March 25, 2009, 08:04:28 PM »

Remove the spark plug wire from the blackend plug and verify that no change is running is observed while the car is in shitty-run condition. BTW, the cylinder closest to the radiator is #1.
Check the condition of the spark to #1 when it's acting up. My hunch is a bad coil.

bbarnumboy · « **Reply #3 on:** March 25, 2009, 09:46:43 PM »

i was thinking that at first but i heard coils normally act up at hot tempurature. it does not do it long enough to diagnose with the plug wire, but i will try that out. the wires are only 1 1/2 years old. and it has always had a slight missfire/hickup at idle even when warm. i will try this and get back thanks

anymore ideas are welcomed. i just ran fuel injector cleaner through the vehicle as well and that wasn't it.

xwill112x · « **Reply #4 on:** March 26, 2009, 08:07:46 AM »

i had same issue's

i just change my plugs when this happens and my problems are fixed.

bbarnumboy · « **Reply #5 on:** March 26, 2009, 07:19:41 PM »

i did change the plugs and 2 days later it came back..

i think i fixed it. there was still some oil in the plug channel and on the plug wire, i think it was grounding out. i pulled the plug out cleaned it and the channel and the wire with maf sensor cleaner. and it works fine, i will see tonight how it works on the cold startup. thanks guys

bbarnumboy · « **Reply #6 on:** April 09, 2009, 03:00:20 PM »

well did a compression test and this could be my idle issue.

cyl 2 190psi
cyl 2 120psi
cyl 3 180psi
cyl 4 200psi

txleadfoot · « **Reply #7 on:** April 09, 2009, 03:29:26 PM »

120, ouch.

bbarnumboy · « **Reply #8 on:** April 13, 2009, 02:41:16 AM »

found theproblem, i have a blown head gasket yet again, i am loosing coolant into cyl#2 that is the reason for the thick steamy exhaust. looks like the heads coming off again :-) yay