Sometimes the Blazer Starts, and Sometimes it Doesn't

We have a 1990 Chevy Blazer.

Engine has always been very reliable, till this past winter when DC had the 3-foot blizzard. At that point, we discovered it wouldn’t start. We figured it was the battery. We just let it sit till all the snow melted. Then we tried it again and it started no problem



Since then, it is intermittently DEAD and other times FINE.

– DEAD = open door, no dome light. Turn Key, no sound at all. Nothing.

– FINE = lights work, car starts, just like it was brand new



This is not entirely random

We have noticed the following patterns

– It never starts after it rains. You need to wait for a day of sun

– It will sometimes start if you open the hood and jiggle some things, or even slam the car door really hard.



It seems like something is loose or frayed or not quite connected, but we’ve tried to tighten everything we can get our hands on and the issue continues.



Ideas???

Start by removing both battery cables and clean them both as well as the battery connections. Check both cables to see if they are securely connected one to a ground and the other to the starter. Check for a braided ground from the engine to ground. If not…I would install one.

Also check and clean the connection at the starter motor.