gusgus

I have changed the plugs and wires on the car and replaced the optispark. On two occasions the temps rose to the 70's and the humidity was high . The Vette would not start, it backfired some but simply would not start. The weather changed and it started easily as usual as the humidity dissipated. The car runs smoothly all other times. Suggestions as to the reason?

drcook

That could be the coil having issues. Not saying definitively it is, but I have seen that a lot.

Unplug the underhood light and try to start it in the dark (have a helper try to start it) and see if you see a glow or anything around the coil (or anywhere under the hood for that matter) where moisture is giving the electric a path to escape.

Ed Ramberger

If you want to check the coil just mist it with water and see if it won't start.

car addict

Does it act like it might fire - bump a time or two - right after you quit cranking it?

81c3

Sounds like it could be some condensation building up in the optispark....

gusgus

Yes, it almost starts and does "chug" while the starter is engaged

car addict

Another Chevy I have (350 VORTEC, not a Vette) had this problem every time it rained or the humidity was very high. The culprit was ignition module. Cranked with no fire until I'd stop cranking, then it'd act like it was going to start - but just a few bumps. Don't know how you'd test that, though.

GraphMan

Don't stop! What was the problem & solution? I am having the exact same issue with my 1995 LT1.