I found this not too far from my house which doesn't happen too often for me. It does have a little rust but nothing that can't be tamed. It has been sitting for a while so I am still in the process of getting it waxed up and cleaned out. The guy that had it parked it because it quit running right and he didn't have time to get it fixed. It will start but it will not stay running. I have started to diagnose the problem but haven't made much progress yet. When it starts up it will not idle at all. If I work the pedal it will keep it going but it will die as soon as I stop. I just thought I would post some pics for all the E28 people out there. Hopefully I can get it running and back on the road soon.
http://i139.photobucket.com/albums/q316/neogenDVE/HPIM0507.jpg
http://i139.photobucket.com/albums/q316/neogenDVE/HPIM0512.jpg

http://i139.photobucket.com/albums/q316/neogenDVE/HPIM0511.jpg
http://i139.photobucket.com/albums/q316/neogenDVE/HPIM0509.jpg

Try cleaning the idle control valve.

Actually you were almost right on the money..... Earlier today I was doing some more troubleshooting and just happened to look at the back side of the engine and the hose going into the Idle valve was completely not attached to it. I plugged it up and it started right up. It was probably the easiest fix I have ever ended up doing. The guy that owned the car actually parked it three years ago because of that problem. I fixed it in about 2 minutes.