Rain Rain Go Away

I have trouble with my Chev. Blazer. Everytime it rains or there is a HEAVY dew the car will not start. It cranks like it is trying but you can't start it. When the sun comes out and it drys up then the car will start. I've replaced the distributer and the distributer cap and that didn't work. Any suggestions on what could be wrong?

Jeez.. someone more knowledgeable may have a better idea than I, but my shot in the dark would be air filter. Free to check and cheap to replace anyway, so it's probably worth your while regardless.

Have you ever noticed water inside your engine bay while this dew is still present? You might have some condensation on an electrical component (solenoid or something of the sort).

What year/engine size is your blazer, and what is the 8th digit of your VIN?

You might want to change the plug wires too :banghead:

Sounds like an ignition module, BUT, if you have replaced the entire distributor (new one I hope) that rule that out. Ditto on cap. Wires - very possible. Since you do not advise year or motor etc, hard to go further, but, if you engine has a MAF sensor I have seen those get dirty and cause same symptoms on my company's GM trucks. Hard starts when damp. Advise year, motor, vin type etc. to help get answers.

instead of throwing parts at it, buy a cheap spark tester, and the next time it doesnt start due to rain, check for spark. If there is none, you know its ignition related. Then you can start throwing parts at it. I myself am not convinced. Water can get anywhere and cause corrosion. Maybe just spend the day looking at sensor plugs. spraying them with wd-40 and reseating them. A lot of times this helps. Also look for any that are missing their rubber seals. when it doesnt start does the check engine light come on by chance? Have the computer scanned for codes.

I had this same problem with my s10 p/u. It was the wires. Here's an easy test -when you get the truck running take a spray bottle and MIST water around the wires and watch for arching. This obviously will work best in the dark whether it's night or the garage. I guess you could even try this while you're having problems too - just check for archs. I ended up having hairline cracks in the wires and they were grounding out to the block.

1998 blazer 4.3 engine 8th # on the vin is W

Also check your engine and transmision ground.