I have a 1994 850T with 193,000 miles. I had an intermittent idle speed for a while. I recently changed the air cleaner. About a week after that the car stalled at a light but I was able to restart it instantly. It set the MAF code. I checked that out and replaced the MAF. The idle is better but still seems like it wants to die. Acceleration is great and otherwise drives fine. I also replaced the spark plugs.
Is this an IAC or throttle body problem? I have some info from alldata but I am not sure where to begin.
Thanks.

I followed your directions. First I disconnected the battery and removed the IAC. I used MAF cleaner that I had to clean the valve and reinstalled the IAC. I found that the repair garage I use had removed this at some time in the past and I found a missing hose clamp on the other end of the short hose. I put on a hose aclamp I had in my box of clamps. The car idles fine now.
Now I hear a rattle/vibration when I rev it slightly, may be the steering pump which is original.
Thank you very much for your help. I understand the IAC is approx. $180 to replace.

Get a can of throttle body cleaner and clean the idle control until it shines! I used a small tooth brush and pipe cleaners to get to the hard to reach areas.

I also held the IC valve over a smallish can to catch the excess cleaner, which then cleaned the toothbrush and the hose. I also used wirecutter type pliers to squeeze the clamps back together.

Klaus