Help with rough idle

[Blendercloud]

Hey guys! I've got an '89 325iX with a stock M20. It has a really difficult time staying running when cold, but even more annoying is the really rough idle when it gets a bit warmed up. I've included a link below (sorry the video is sideways!).

http://youtu.be/aezjsXgO8Ns

I'm looking for help on what this could be. I've been driving the car like this for more than a year, seemingly without any adverse affects. But now I'm getting ready to sell it and I'd like to iron out this wrinkle beforehand.

Thanks for your suggestions!
Chris

[Blendercloud]

Bump

Any help or suggestions would be appreciated. Thanks!

[NoM54me]

Didn't watch the video, but the idles-rough-when-cold symptom frequently points to faulty coolant temp sensor, or bad/broken CTS wires.

[Blendercloud]

Thanks a lot for your response! I'll check those out and report back.

[Blendercloud]

Sadly, replacing that switch was no improvement. Time to scour the engine bay for vacuum leaks.

[Cabriolet]

Chris you have an air leak or bad afm. take it to a shop to get a smoke test done. that will check for leaks.
also if you haven't, replace your spark plugs with the correct 2 options. bosch w8lcr or ngk zgr5a.