Just in case it was something electronic, I had the dealer do some diagnostics on the car. The PCM/related sensors are fine, so I'm reduced to the Ignition Control Module or, once again, the distributor being out of time. I reused the ICM from the car after my rebuild (new coil though), so I've ordered a new one just to see if it helps. I didn't even think an ICM could cause my starting issue, but apparently it can. My new module will be in tonight, so I'm going to try the easy route first. However, I expect I'll wind up pulling the optispark for the fourth time in two weeks. I can't imagine how I could install two different distributors incorrectly across three installations...I don't know if it's worth checking the indexing and reinstalling this distributor again (I just got the latest one on Friday) or if I should save myself the uncertainty and buy an AC Delco unit.

Could I damage anything if I started the motor without the water pump connected? I'm worried that the W/P driveshaft won't be sufficiently supported without the pump on and ruin the seal I just replaced. I hate re-assembling the whole deal if the distributor isn't going to work.

 

Well, it turns out I suck at installing optisparks! I had the thing indexed correctly on the engine side, but not on the distributor side. I'm amazed at how easily that keyed shaft went in incorrectly. At any rate, the car runs beautifully again and I have a nice new ICM.