e36 M3 Cold Start Problem
 

When starting cold my ’97 M3 coupe has stumbled a little for the last few months, but this morning the problem was significantly worse. It was about 35 degrees out and once started it would idle very rough or shut off entirely. It took several attempts to get it started and it continued to idle rough until it warmed up. Once warm it ran fine. I’m sure I’m not the first to have this problem, if you have any info or recommendations sent it my way, I appreciate it.

Hmmm, maybe the idle control valve? Ambient temp sensor?

Bulletin
 

BMW has a Service Info Bulletin for this cold start problem
Bulletin# 12 02 99
The fix is reprogram the DME
This may be a dealer only type of reprogram.
Dealer can run your vin# to see if it has already been done to your car.

Another possibility could be leaking inj, worn spark plugs, vac leak, etc,etc
SmileWavy

Thanks for that! I need to start compiling a dealer bulletin database...