My van wont start whenever the air is damp?

Hi Try this on dry day engine starting get a spray bottle with water. Spray then Ignition Control Module they try and start if starts do same to crankshaft sensor. See diagrams

Let me know Thanks for donate

Thanks alot, man! You probably saved me hundreds that a mechanic would have charged. I sprayed water on the crankshaft sensor on a dry day like you advised and it didn't start...put a new one on and sprayed it and it started right up. The real test will be in a few hours when it rains, but I'm pretty sure that fixed it. You know what you're doing! Thanks again.

Glad to have helped Yea could have turned into a Money Pit. Come back if you need help in the future

I was wrong...it is raining today and the van would not start again. The only thing I havent replaced is the ignition control module...any other ideas?

Check out vehicle control module left side engine compartment. See if rain water getting on VCM. pull connectors see if its wet.

I checked out everything i could see without taking it apart..nothing seemed wet..i give up..taking it to a mechanic tomorrow..thanks anyway

I had this problem for years and understand so did GMC trucks.
Somewhere in this period around 2000, GMC went to a low profile distributor.
After a zillion mechanic in several states and a lot of $$$ later I finally found a mechanic who figured it out and a solution.
What he did was put dialectic grease all around distributor. Then he saw that air conditioning lines went directly over the distributor causing condensation so he split a garden hose which he covered the lines with.
I have not had any problems since and that was about 4+ years ago.
Hope this helps

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