[nate93]

Hi,

I have a 2011 N55 335i. From a cold start, if I leave the car idles a bit longer then it leads to rough idling and engine light, but if I start driving when it drops to 600-700 rpm then it is fine. After the engine light is thrown, I can turn off the car and turn it back on, then it runs normal.

I think it's the MAF sensor that is not working correctly. I did play with it when I was installing the cold intake but went back to stock after I realized it's a hot intake rather than cold.

Anyone experienced similar symptom and was able to resolve it?

[9krpmrx8]

What code was the car showing? Make sure there are no intake leaks, clean the MAF and reset adaptations since you switched back to the stock intake.

[nate93]

Hi,

Actually I don't think its the MAF anymore.

When I pulled the code I got 2BEE and 2BF8.


Now it is down to HFPF or fuel pump. I just don't know how to diagnose and trace down to one of them, HOPEFULLY not both.

any tips and experiences will be greatly appreciated.

More information.
The car runs fine if I start it up and don't let it idle for too long. If I let it idle for a long period of time. It throws those two codes, misfires, and throw engine light. If I turn it off fully and start it back on, the car runs fine if I again don't let idle for too long. Also, no long cranks like many have described when their HFPF is about to go out, I don't experience that.

Please help!

[Tallicia]

What was the root cause? the Fuel Control Module/EKPM? LPFP? HPFP? Fuel Rail Sensor?