2001 Blazer would not start one Monday last month. I drove it the Saturday before and it ran fine. Rained hard Sunday, would not start Monday morning. Will turn over and I can hear fuel pump, but will not start. It started Tuesday afternoon (Monday and Tuesday were hot dry days). I have been driving it on and off and it has been starting fine. Got in this morning and it would not start again. I did not think about the rain until this morning. It rained hard Sunday and is still raining. So, water has to be the problem. Maybe the ground is shorting out? I don't know where to start.

 

Sounds like a bad distributor cap. Hard starting in damp conditions is a classic sign. I would change out the rotor at the same time.

 

Two other things:
1. Remove the distributor cap and look at the base plate. If there is a small vent hole, make sure it is not clogged.

2. After dark take a spray bottle and lightly mist the plug wires while the engine is running. If you see arcing, then replace the wire(s).

 

Great dry day in Georgia. Blazer starting great. Sprayed the distributor cap with water and waited a few minutes and now it won't start. Well, I guess the mechanic that replaced the cap about a year ago DID NOT use AC Delco! Will get AC Delco today! Thanks! Original cap lasted almost 10 years! No more cheap parts!

 

Blazers are very partiular about parts. Its always best to stick with delhpi or delco.

 

Pulled the cap an could not find a crack and did not see any water under the cap. Shouldn't I be able to find where the water is getting in? Also, when taking it off, noticed that it has play in like it is not fitting just right. Not rotating or anything like that, just like it is not tightened but it is.

 

Any signs of arching or corrosion? It still sounds like a bad cap and rotor. Might want to take it to a shop and have them make sure the distributor is at 0 after you change the cap and rotor.