ME

Marcel E.

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BMW Z4 Misfire Cylinder 2 | BMW

Dear colleagues,

I'm starting to despair, a friend's Z4 is really giving me a headache.

The following problem: when I start the car (cold start) it runs very rough. As soon as I warm up the car, the engine starts to "clatter" and "pop" out of the exhaust. However, this is not noticeable during normal or slightly faster driving, but if you rev it up a bit, the CEL suddenly comes on and spits out the error "Misfire cylinder 2".

I ask for your help! Thanks in advance!

Already checked

Engine misfires on cylinder 2 after cold start and when revving at high RPM.

Error codes

  • 0029CE
#Engine

BMW

3.0 si

Schaltgetriebe

💬10

Own solution

Marcel E.

Was it engine failure 😂

Comments (10)

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  1. Franz K.

    That sounds a lot like an injector or fuel nozzle issue. I had the same problem with my 1 Series. Despite only 90,000 km, the injector was leaking. How many km has the car done?

    6
  3. Christian G.

    Unscrew the spark plugs. Inspect them and install the spark plug from cylinder 3 into cylinder 1. If it has a single spark coil, swap the coil on cylinder 6. Then try the test again. Scan for fault codes. Does the fault remain on cylinder 3? If yes, check the fuel injectors. And have the compression checked.

    1
  4. Franz K.

    The problem is on cyl. 2 😉. Plugs and coils are new. He already wrote that. 😋. There's not much left. But comparing the spark plug picture from cylinder 2 with one of the other spark plugs can't hurt. Spark plug black -> too much fuel. Spark plug white -> too little fuel. In my case, the spark plug was wet despite the new coil and spark plug. It was quite clearly the injector completely broken.

  5. Christian G.

    Even new coils can cause problems. Or spark plugs. The probability is low but it exists 🙈.

    But I agree with you, I meant cylinder 2 of course 🤦‍♂️.

    Then you could also swap the injectors 😅

  7. Christian R.

    Measure a pressure loss test and the injector cylinder 2. Regards

  8. Reiner

    Check the injection of cylinder 2 (spray pattern), if necessary, exchange with other cylinders to see if the error moves.

    1
  9. Faraj I.

    Check or have the valve timing checked.

  10. Marcel E.

    Thank you for all your help! Outstanding! I will first replace the fuel injectors and see if the fault migrates; if it does, everything is clear. If it is still not better, I will have the compression checked and the timing.

    1
  11. Marcel E.

    So the fuel injector was replaced, the error was cleared. The CEL does not come on anymore, but the idle is still rough 😕 could it still be the MAF sensor?