Need help diagnosing CEL

[weetan]

Hey guys so I’ve been trying to chase down some problems with my car. I’m getting three codes.
- air volume too high
- pcv hose faulty or disconnected
- fuel mixture too rich on both banks
I have replaced just about everything it seems like.
I’ve replaced:
- pcv hoses
- spark plugs and ignition coils
- high pressure fuel pumps
- injectors
- down stream O2 sensors
The car has been smoke tested multiple times with no leaks. I removed the tune and the dinan intake with no luck as well. The car has stock downpipes. If anyone has a clue what this could be it would be greatly appreciated.

[KurtsM5]

Upstream 02 sensors?

[weetan]

I ohmed out the upstream and they seemed good still. 3-4 ohms on each bank. I got 10 ohms for the downstreams so I replaced those.

[Grantgkg]

Remove the mass air flow meters and see if they are covered in oil, clean them off with mass air flow cleaner. you also replaced the fuel injectors, did you use the correct fuel injectors? because you can get EU6 or EU5. If you installed the incorrect ones for the DME you can get some strange issues. The EU6 injectors have all the same calibration numbers {215}. The EU5 injectors have variable injector calibrations and those numbers will have be be changed in the dme's to make them work properly. Let me know your findings.

[M5Rick]

Replaced practically everything, what year is the M5 ?

[Blaxwil]

Try cleaning both MAF’s with CRC Mass Air Flow Sensor Cleaner. When was the last time you replaced your air filters? Do you have an intake? If so, buy new filters instead of just cleaning them. Lastly, check to be sure the connections on the PCV’s are tight. If all this fails, then buy new MAF’s and check the inlet side of both turbos.

You have an air flow issue. So anything related needs to be replaced during troubleshooting. You did all the hardest and most expensive stuff already.

[weetan]

Originally Posted by M5Rick

Replaced practically everything, what year is the M5 ?

It’s a 2012 imported from Canada.

[weetan]

Originally Posted by Grantgkg

Remove the mass air flow meters and see if they are covered in oil, clean them off with mass air flow cleaner. you also replaced the fuel injectors, did you use the correct fuel injectors? because you can get EU6 or EU5. If you installed the incorrect ones for the DME you can get some strange issues. The EU6 injectors have all the same calibration numbers {215}. The EU5 injectors have variable injector calibrations and those numbers will have be be changed in the dme's to make them work properly. Let me know your findings.

Since the car is a 2012 they were replaced with eu5s.

[weetan]

Originally Posted by Blaxwil

Try cleaning both MAF’s with CRC Mass Air Flow Sensor Cleaner. When was the last time you replaced your air filters? Do you have an intake? If so, buy new filters instead of just cleaning them. Lastly, check to be sure the connections on the PCV’s are tight. If all this fails, then buy new MAF’s and check the inlet side of both turbos.

You have an air flow issue. So anything related needs to be replaced during troubleshooting. You did all the hardest and most expensive stuff already.

I have a dinan intake and the filters were just recently replaced once I started having this issue. I’ve cleaned the mafs but it might be time for new ones.

[JLOA]

Originally Posted by weetan

Hey guys so I’ve been trying to chase down some problems with my car. I’m getting three codes.
- air volume too high
- pcv hose faulty or disconnected
- fuel mixture too rich on both banks
I have replaced just about everything it seems like.
I’ve replaced:
- pcv hoses
- spark plugs and ignition coils
- high pressure fuel pumps
- injectors
- down stream O2 sensors
The car has been smoke tested multiple times with no leaks. I removed the tune and the dinan intake with no luck as well. The car has stock downpipes. If anyone has a clue what this could be it would be greatly appreciated.

my 2014 m5 comp started running really rough last month, I started changing everything like you did and also cleaned my MAF sensors. My car would stall out of nowhere and rpm was bouncing around while idle, well I ordered two new MAF sensors and after driving it for 10 mins the car runs like new.. I also ordered them from rock auto.com cause dealer wanted alot of money for them

[weetan]

Originally Posted by JLOA

my 2014 m5 comp started running really rough last month, I started changing everything like you did and also cleaned my MAF sensors. My car would stall out of nowhere and rpm was bouncing around while idle, well I ordered two new MAF sensors and after driving it for 10 mins the car runs like new.. I also ordered them from rock auto.com cause dealer wanted alot of money for them

It was the mafs. Don’t know what caused them to crap out but replacing them worked. Thanks.