Still no clue why this B230FT won't start (cranks strongly and occasionally shudders like it want to start)

Is there a way to test the power stage? Could missing one of the two mounting bolts allow an intermittant no-start?
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1989 740Ti 1986 240DL 1984 244GL

If the hall sensor (which I think 89 turbos have)is working and the coil, dist. and leads are OK then you might suspect the power stage - there's nothing else in the chain to prevent a spark apart from an open circuit. Hall sensor can be tested with voltmeter - FAQ's detail this. BTW it isn't just the 5volt level off the hall that matters, it's the low voltage too if you need to do this test. I assume your main fuel pump is operating?

BillB

I pulled the return line off the FPR and got flow when I cranked the engine. I don't hear the main fuel pump run when I turn the switch to "ON" before trying to start. I DO hear it after I stop cranking.

Also, after carefully spraying something flammable into the intake past the throttle place, the engine does ignite it.

I am beginning to suspect water in the fuel tank. Although I have added a bottle of "Dry Gas", the car is facing upill and on jack stands for the moment. I think the dry gas won't help yet.
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1989 740Ti 1986 240DL 1984 244GL

If the power stage fails, you should have no spark. It uses the fender as a heat sink, so maybe a poor thermal connection caused a problem.

Well, I do have spark, though. The engine will "cough" as if trying to start. I carefully sprayed something flammable into the intake and it was quickly consumed when I turned over the engine.

Gotta be ssome kind of fuel delivery problem. I do get flow out the fuel return line from the FPR.
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1989 740Ti 1986 240DL 1984 244GL