[jc2078]

Hi guys

I have a misfire with SES light that comes on. The misfire only happens on cold starts. The car starts shaking, does not accelerate, and throws an SES. However when I pull over and turn off the car and turn it back on, the misfire is gone instantly (and so is the SES). This has happened 3 times now. I already changed the spark plugs, no fix

so i'm down to coils or injectors. Seems electrical but not sure coils do this?

09 n54 335i 40k miles

Thanks

[alexg212]

If x amount of misfires in y amount of time, that car will throw an SES and turn off that cylinder. Restarting and it going away is normal. But there should be misfire codes stored letting you know what cylinder the issues are on.

[Lshaw]

First thing is first, read the stickies on this subsection. Also usually a Google search will bring up every thing you need to know about the codes/symptoms and more.

Since you changed your plugs, usually the next culprit are the coils. But since you misfire on cold starts only, sounds like a leaky injector. Pull the codes check which cyl., check that plug for fouling.

[ferocity02]

What codes are you getting? Check the code and see which cylinder it is, then swap that cylinder's coil with another cylinder. Wait until it happens again, then check the code and see if the code switched cylinders. If the code follows the coil then it's the coil. If not then it's probably the injector.

[joeinsd]

Had the same issue last year. Dealer replaced (under CPO) coils, plugs, then injectors (in that order, 3 visits) and it was fine after.

[ritzzzzzwik]

I'm sorry but no one would be able to help w/o codes. If you dont have the means to read codes, then take it to the dealer. Codes will be stored in the ECU. I assume at 40K you still have factory warranty.

[jc2078]

Here are the codes. It's 3 cylinders so not sure what to do. Out of warranty since it's an 2009

[jc2078]

Plugs are all clean when I changed them last week. One was a bit darker but not much

[tc535i]

Might be the o2 for bank 1 since they're all misfiring

[ferocity02]

Swap cylinders 1-3 coils to 4-6 and see if the codes follow. If they do, replace all 3 of those coils.

[muncie21]

Mosfets

[limitdown]

It might be the precat O2 sensor for bank1 since that entire bank is misfiring

[tc535i]

Originally Posted by muncie21

Mosfets

If swapping o2 doesn't help, this is the next likely culprit

[=C=]

I started getting misfires when i WOT in 3rd gear. Coils and spark plugs already replaced. I guess injector is next?

Cobb ap tune

[jc2078]

Well I cleared the misfires changed packs 1-3 4-6. Now I have this. Can't drive the car the throttle just goes up and down 1-2k rpm

[jc2078]

It was due to adapt reset figured it out

[mojobmw_e90]

Originally Posted by jc2078

Well I cleared the misfires changed packs 1-3 4-6. Now I have this. Can't drive the car the throttle just goes up and down 1-2k rpm

Sounds like u reset the throttle adoptions as well. Let the car learn those before driving. Let it idle for a few mins and drive slowely around

[muncie21]

Did swapping the coils fix the problem?

[ferocity02]

After resetting adaptations you need to clear codes and/or let it sit for a bit otherwise you'll get the surging idle issue.

[jc2078]

It hasn't thrown a SES code again so I can't tell what is causing the misfire so I'll just have to wait

[jc2078]

Codes came back (cylinder 1-3 misfire) same as above. Any chance this is the low fuel pressure sensor since I have code 29f3 too? I have had that code for a year tho

[BRD1234]

I have the 293F Code as well.
It's most likely the low fuel pressure sensor.
I have ordered the part and will let you know if this solves my problem, my symptoms are exactly like yours.