Another sputtering and misfire thread (I've searched it all)

[APhelps89]

Ok guys heres what I'm looking at. Just rescued an 86 325 from an anti-terrorism specialty training center, which they dropped an m20 from an 84 528e in. There are multiple symptoms, which I feel are all linked together in some way but some of these I have never seen in my e30 experiences.

Symptoms as follows:
-Really rough idle
-Sputtering and misfire at lower range RPM but when rolling on throttle revs out fine
-Running stupid rich, like white smoke blowback stupid rich
-White smoke leaking from exhaust somewhere
-When started you have to keep it above (guessing) 2k until it settles to be able to idle normally
-Tach will jump up at start then immediately quit working
-Check light for engine oil comes on when you touch the brakes? But when you touch the brakes the idle smooths out some

Slowly troubleshooting everything but funds are minimal and its still out in the field at the training center, Ive searched everything but the oil light is what is throwing me off the most. Thanks in advance

[Simple_Smith]

White smoke indicates coolant... Black smoke would be stupid rich

[dnguyen1963]

Where to begin...HG is probably blown, vacuum leaks, SI board, the wiring is probably all screwed up. But at least you will have fun re-building this baby.