Hello All,
I am having difficulties with my 91 745, b230F. This problem just began in the past few days, so here goes. When driving the car after a while (20-30 mins or so) it would not hold it's idle. It would run fine until well into driving, and then would just die. Applying a touch of throttle keeps it going. Now, it won't idle at startup either. I have replaced the plug wires, as the plugs are fairly new and in good shape, and have removed and cleaned the throttle body, it is now spotless. The FAQ is kinda confusing as it tries to guide you based on known problems, but where do I start? Thanks for the help in advance.

Keith

Sounds like the idle air valve isn't opening. Remove it and give it a good cleaning. Also check that the throttle position switch is adjusted properly.

IAV would be my best guess, too. Clean your throttle body at the same time. Check the FAQs for details about how to clean both.

Suggest you get a can of CRC Mass Air Flow Cleaner, pull off the AMM (faster than changing an air filter) and spray the heck out of it. This worked great for me on a stalling-at-idle problem, just when I was convinced I needed a new and pricey AMM.

Others here have more knowledge -- this is my one magic bullet. Good luck.

Well, thanks for the tip, but my 91 745 has the Regina system on it, so no AMM. Would this be caused by a dirty Air Temperature Sensor? Should I check the MAP sensor? I have experienced these going bad in a Mercedes, but they seemed to just die, not gradually like my problems occurred. Any help is appreciated.

Keith