My 2000 Blazer 4.3 4wd runs GREAT and now has 342G miles! My problem is on rainy,damp etc. mornings it dosen't want to start. After multiple starts and just about killing the battery it will start. I've had to start running a light under the hood at night to keep everything warm and dry and sure enough it starts when I do this. I've changed caps, plugs, wires, coils, modulars ... you name it. What am I missing here? Thanks ! Jim

 

Look under the distributor cap on the bottom plate. If there is a vent there it may be plugged with debris holding in moisture.

 

The lower housing could have a crack allowing moister to seep in. Since you have replaced the other components and the problem still occurs.

 

when it is in a starting condition leave it running and get a spray bottle and start to mist water around the engine bay pay attention to were the water is landing and when it starts to act up.

 

no screen ... any other thoughts? Jim

 

I have the same exact problem.
My 2001 won't start on damp mornings.
No luck with above recomendations so far.
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