This may be a stupid question, but I'm used to working on my 81 Z28 which is pretty much all mechanical rather than computer controlled like my 94 Z28... So I'm new to all this... I just replaced the water pump and optispark... When I crank the engine, it turns over slowly... It acts like the timing is off... After it gets started it runs perfectly... I had the car sitting a few days and I know the battery is a possiblity... The gauge reads below the halfway point... Assuming that the optispark is good, is there any way the timing could be slightly screwed up by my install or would the computer over ride this and adjust the timing so it would crank normally. ...and by the way, what dumb engineer puts a moisture sensative device like a distributor under a water pump? At least they should have a shield of some sort or even a moisture proof boot surrounding it.

 

Yeah, I think the opti goes on only one way and it is really really hard to screw up your timing. My first guess is a tired battery, or tired starter, but battery is my first guess. Yeah, that was a poor engineering job. Almost makes you wonder if they did that on purpose so people would be taking them back to get them repaired a lot, lol. I agree that they could have devised some sort of cover to keep coolant out for the most part if the waterpump failed. Not sure how this would affect general moisture though, because some might condense inside the cover when the engine gets warm.

Maybe someone else can chime in here but I'd think it's probably your battery.