Check engine light codes po170 and po173...Can anyone tell me what these codes mean? On 1999 540i...Please help...
There was a very similar post on another forum recently. Rather than repeating what was said...here's the link... http://forums.bimmerforums.com/forum/showthread.php?p=13066912#post13066912&highlight=po170 Hope this helps!
check engine light.. Thanks for the link...will check it out... I have 60,000 miles on the car and it runs great. It starts fine and when driven no hesitations..I took the cold air intake (dinan) apart cleaned it all up nice also cleaned mass air flow. Disconnected battery to reset light...1 day later light is on again.....thanks again....wish me luck
It means the fuel trim is outside the specified range and you are running too rich or too lean. This could be caused by a number of things: Mass Air Flow Sensor, oxygen sensors, ignition misfires, fuel injector problems, etc. but I would start with the Mass AIr Flow Sensor. I would buy a can of MAF cleaner and just pop off the air cleaner and loosen the hose clamp and then just slip off the MAF Sensor and give it a few shots of the cleaner (being careful not to touch the tiny expensive platinum leads with ANYTHING other than the cleaner fluid - and remember to let it dry by the way because the cleaner is extremely flamable). Then put it back on and start her up and see if that fixes the problem. A dirty MAF can misread the airflow volume and cause your onboard computer to adjust your fuel mixture way outside the specified range.
check engine light my light came on when my gas cap was closed tight, that created a fuel pressure drop and the light came on, now does any one know how to reset it?
Start your own thread for questions for the best visibility. If you have an E34 wagon, just wait and the CEL will go out by itself if the problem was caused by the gas cap and has been resolved. Otherwise, you can disconnect your battery (make sure you have your radio code and know what you are doing.)
