This is a problem that's been going on for quite some time, I just haven't bothered about it until now.
My '89 740 Turbo Wagon with 110K miles starts up nicely in warm and cold weather (unless after a long rain/snow, which is a different topic - I think). When I start the engine, the RPMs go up as usual, and then settles down into normal 1000 rmp range. Then, after about 10 seconds or so, the RPMs go down into the hundreds, the engine shakes as if it tries to catch itself, and it dies. If I then start the car again, it starts fine, although it does shake a bit at first when going below 800. The longer the engine runs, the better this gets - after driving a few minutes the problem goes away completely.

Reading the FAQ points me to a clogged or faulty Idle Control Valve, or as the FAQ calls it, IAC. Since I can get this item almost new right now for very cheap, I want to know if replacing this valve is a DIY job, and if so, what are the steps to replace it. Or does the problem lie elsewhere?

Can anyone with experience in this matter help? Thanks!!