I am having a problem with my E38 and need some help. My car Bucks and goes into Engine fail safe mode when you accelerate to the point where the car goes into Passing gear( or climbing and steep hill and accelerate). It does not red line; it is just under a heaver load. I took it to the dealer and was told it had two BMW codes set. One was the MAF sensor And the other was the throttle body failure. Both were replaced yet I am still having the same problem. Does anyone have any ideas where I should look? I am thinking it is a fuel delivery issue (fuel filter, fuel pump).Has anyone had the same issue? Thanks for any help.
Year and model? There are a few things that can cause this, but I had to replace the ECU on a 540 to cure these same symptoms once, while a different car had these symptoms and the cause was something obstructing the throttle body.
JFYI, it was a 2000 540i that needed an ECU. I'll ask if the boss can remember any details on that one but most of it has left my brain.
I have received some feed back on another forum that it may be a clogged catalytic converter Has any one had that issue?
I have not had that problem with a customer car, but there is a simple tool that checks the back pressure by screwing it in place of the front O2 sensor and running the car. You will probalby need to take it to a shop to diagnose it. I always recommend qualified independents.