I have had my car now for 4 years--it has never passed emissions. I have had a new O2 sensor put in as well as taken it to an import specialist to 'repair.' They got the car to run fine at idle but in Wisconsin they do a running chassis test. I also put in new cats which are problably dead again because the car runs so rich.
I think they adjusted the idle mixture and I added to the problem by adjusting the whole fuel curve so that I retarded the timing and fuel by 5% (I'd have to look at the chart but I think that's how much it was)
I now have another problem were, only at idle, the engine wants to overheat.
Can anyone give me advice--I'm going to set the fuel curve back to where it was so that it is rich everywhere but, what do I do???
I LOVE this car and probaby will never sell it but I am a my breaking point over this emissions problem--its cost me $200-$400 every other year worth of work on my car to get an exemption from the state........PLEASE help me!!!
Have anyone else had these problems?
Dave

How do you know that it is running lean at idle, just that it overheats, or have you actually metered it? Your car could overheat at idle because of an electrical problem with the aux fan, or the clutch fan.

Dude, you have some problems!
1. FIND A S14 SPECIALIST!
2. Make sure your ECU was not changed to richen thigns up.
3. Replace the fuel pressure regulator, this will cause this condition and make sure you repalce the vacume line.
4. Get a compleat INSP II done! Then make sure they set the TB's and base idle and CO after the vavle adjsutment.
5. Check the blue coolant temp snesor, this tells the ECU what the engine temp is and how much fuel to add.
6. Clean the fuel injectors

Good luck! A good running M3 will make you a lot happier!

Now for the over heating, with the engine warm, get a rolled up news paper and stick it into the fan, if it stops you need a new fan. Also turn on the AC and make sure the AUX fan turn on, the wireing harness for that breaks and needs to be replaced often, if not the resistor on the aux fan may need to be replaced. Both are way cheap.

I just had the 50,000 mile checkup done last Spring,2002(Just turned 60k last week). I just had the fuel regulator and line changed out when I brought it out of storage--I couldn't get her started.
My AC is out--I the bearing in the compressor went out years ago and I just can't bring myself to do the conversion--$$$--especially with bigger problems.
I'm guessing you are right with the fan--I have a friend that specializes in BMW's, he is president of the BMW club. The problem is they do not have any emissions equipment.
If only I could solve this problem, I LOVE my car, but this is starting to kill me. I am almost relieved when winter comes because I just turn the key in my honda and go---bland car but no thought needed.

Thanks for BOTH of your replys, any other thoughts please let me know.............88 M3 - 60,098 miles.........Dave