|Originally posted by sourmash:|
Right. You're probably right. The car was converted to turbo and had coil packs. Hmm. Wonder where the trigger is. Didn't think of to look.
The successors of the 2.8 have crankshaft triggers. In the middle of the crankshaft is a notched wheel. Penetrating the right side of the engine block is a variable reluctance sensor.
These VR sensors would typically interface with the coil-pack module; this presented an "emulated distributor" to the ECU, which I guess eased GM's transition from distributors to coil packs.
There's a good chance your junkyard car had one of these setups.
Eventually, GM outgrew the "emulated distributor" paradigm, and the crankshaft sensor was wired directly to the ECU.