Cylinder 3 Misfire, Related To Air Mass Meter?

[jasonharlos]

I have a '99 328i with 83,000k miles that is periodically misfiring. The check engine light comes on and I get two codes: P0303 (Cylinder 3 misfire), and P1250 (Air/Fuel Mixture, related to Air Mass Meter). It always happens on the same cylinder. Whenever the car starts to misfire, it will stop after I shut off and restart the car. I check the connector on the Air Mass Meter and it appears to be fine. Can anyone provide with some ideas on what to check? It doesn't make sense to me that it would be the spark plug or wire since the car will sometimes run for several days without a problem. Performance does not seem to be affected either.

[Mortiorchis]

Originally posted by jasonharlos@May 17 2005, 08:10 PM
I have a '99 328i with 83,000k miles that is periodically misfiring. The check engine light comes on and I get two codes: P0303 (Cylinder 3 misfire), and P1250 (Air/Fuel Mixture, related to Air Mass Meter). It always happens on the same cylinder. Whenever the car starts to misfire, it will stop after I shut off and restart the car. I check the connector on the Air Mass Meter and it appears to be fine. Can anyone provide with some ideas on what to check? It doesn't make sense to me that it would be the spark plug or wire since the car will sometimes run for several days without a problem. Performance does not seem to be affected either.

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Other people have run into this problem. Your only choice is swapping engines:

[EuRopE1981]

I would check the coil on the cylinder, my car was doing the same thing on cylinder 5

[jasonharlos]

Originally posted by EuRopE1981@May 17 2005, 11:16 PM
I would check the coil on the cylinder, my car was doing the same thing on cylinder 5

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Is there a way to tell if the coil is bad, short of replacing it with a new one?

[Hootie361]

swap the suspect coil with a non-suspect coil. clear the error codes, run the car, shut it off. check the error codes again. if the error followed the suspect coil, voila. if not, it's another problem.

check the spark plug shaft for oil residue while you have the coil out.

[jmaurip]

Originally Posted by Hootie361

swap the suspect coil with a non-suspect coil. clear the error codes, run the car, shut it off. check the error codes again. if the error followed the suspect coil, voila. if not, it's another problem.

check the spark plug shaft for oil residue while you have the coil out.

So what if thier is oil residue?

[FCPGroton]

Originally Posted by jmaurip

So what if thier is oil residue?

That means the coil is bad and leaking oil. If it is not the coil, it could be a bad spark plug.

Also, clean your MAF.

[jmaurip]

Originally Posted by FCPGroton

That means the coil is bad and leaking oil. If it is not the coil, it could be a bad spark plug.

Also, clean your MAF.

what is the MAF, also I meant inside where the pistion is not on the spark plug or plugs. The plugs are clean and new......

[sPoNgE-SA]

You can also check the ohms on the coils, make sure they are all the same ohms