[L1eutenantDan67]

I was driving to school last Friday and at a stop light I was behind an older for explorer, as the light turned green I hit the gas and the check engine light came on and the car started running very rough, gauges all were OK and the system check didn't show anything but the check engine light was on. So I shut the car off, got out and checked under the hood and there were no protruding pistons that decided they wanted to go to space, and all else looked fine. When I got back in the car I started it back up, and everything was normal. Drove it back home slowly and went to school in another car. When I got back I hooked up an OBD scanner and it read that cylinder 1 had a misfire so my first thought was sparkplug/coils. After doing a little research I had come to the conclusion that was the problem but I also thought it could've been the exhaust fumes from the car in front of me, although unlikely. I talked to my friend who has an 06 530 and he had a bad coil but it would be on and off so I decided to drive it this week as a test. Since then the car has driven fine and not done anything like that, even under heavy acceleration. I'm not at all a mechanic so I was wondering if anyone has any ideas as to what it could've been or if it was just a hiccup in the ECU.

[bluewater328]

Could have just been a lot of carbon buildup or that the MAF misjudged things.

Just clear codes and monitor. Did you inspect cylinder 1 yet?

[singhr]

It is most likely a coil - same thing happened to me - dealer replaced all coils (under warranty) and no more misfires.

[ducatiti]

Originally Posted by singhr

It is most likely a coil - same thing happened to me - dealer replaced all coils (under warranty) and no more misfires.

Under extended warranty?

[singhr]

Originally Posted by ducatiti

Under extended warranty?

I believe that it was under the SULEV warranty - N51 motor - but I had extended warranty as well at the time. The misfires would happen randomly usually under hard accel - all would be fine once the car was restarted. common issue on these boards.

[chadjones99]

my 2011 328I with about 80 or 90 K on it started missing under a hard load ( hard acceleration ) . I bought new plugs and coil packs just because, and it runs like new no more miss fire, the plugs on these cars ( I think just about all BMWs ) don't last very long maybe 50K and you need plugs and coil packs last about 80K ISH so how many miles on your car sense last spark plug replacement ? And on a side note the water pumps don't last much over 70 to 90 K also

[L1eutenantDan67]

Originally Posted by chadjones99

my 2011 328I with about 80 or 90 K on it started missing under a hard load ( hard acceleration ) . I bought new plugs and coil packs just because, and it runs like new no more miss fire, the plugs on these cars ( I think just about all BMWs ) don't last very long maybe 50K and you need plugs and coil packs last about 80K ISH so how many miles on your car sense last spark plug replacement ? And on a side note the water pumps don't last much over 70 to 90 K also

The car has 95k on it and I bought it with 92, the previous owner didn't know much about it and didn't have any records sadly

[L1eutenantDan67]

Originally Posted by bluewater328

Could have just been a lot of carbon buildup or that the MAF misjudged things.

Just clear codes and monitor. Did you inspect cylinder 1 yet?

What is MAF? not sure how I would inspect it, I haven't pulled anything out yet it's just been too cold to work on things.

[bluewater328]

Originally Posted by L1eutenantDan67

What is MAF? not sure how I would inspect it, I haven't pulled anything out yet it's just been too cold to work on things.

Well if it was the Mass AirFlow sensor then you'd have more problems with stumbling than you're saying (in a way, consistently inconsistent).

Check the plugs and coils first. Easy first step and hopefully your answer. Plugs for a 328 are rated till 100k, but if you've gone 80k+ I'd consider changing anyway.

[L1eutenantDan67]

Originally Posted by bluewater328

Well if it was the Mass AirFlow sensor then you'd have more problems with stumbling than you're saying (in a way, consistently inconsistent).

Check the plugs and coils first. Easy first step and hopefully your answer. Plugs for a 328 are rated till 100k, but if you've gone 80k+ I'd consider changing anyway.

Alright Will do.

[kevink0000]

Just posting here since I am new. 2011 328i. 117k miles. Had a strange misfire that would only manifest when car was cornering, or braking and then with throttle suddenly applied. If car was idling on a hill pointing up, no problem, if pointing down, then misfire would show. No codes initially. Then #6 misfire showed briefly and went away. Then #4 showed and went away. Seemed like water in fuel, and showed up when we had a LOT of rain this season. Bad fuel seemed to be problem since it seemed to be motion or position related. Pulled coils and checked, all looked fine, no oil leaks into plug well, etc. Plugs were new about 10k miles ago. Looked like original coils. Was stumped for a while as code never came back for a few thousand miles, but misfire would persist, enough to cause rough running under certain conditions. Finally misfire got worse. Pulled coils again, looked fine, but #6 smelled strong of silicone, others not far behind. Bosch coil, so silicone encased. Replaced all coils, problem gone. Marginal coil was misfiring due in part to motion of car. Sounds weird, but smell test would have located problem a few thousand miles ago.

[dylane_92]

If you want to see if you can replicate it put it in 5th/6th gear at low speeds and give it a lot of gas. That would cause my coil to misfire

[dmatre]

If you want to narrow it down before spending $$$, then swap the coils between #1 and #2. Then, if/when it happens again check your codes. If misfire moved to #2, then replace the coil. If it stayed at #1 then plugs would be the next thing to check.

Good luck.