1990 850i when I run my ac it runs great. Problem water left on garage floor a few minutes later has some sort of oily residue in it is this normal or am I just an 850 novice.

It may be dripping down the sides of the transmission and collecting oily residue as it does.

Not sure exactly where the drain is though. I have not looked for it specifically.

Thanks Again Terry. I have looked under car looks like it comes directly out of hole just under the driver side door just past the driver side front wheel.