It will not start when it is damp outside, or rainy?

1997 CHEVROLET S-10
150,000 MILES • 4.3L • V6 • 4WD • AUTOMATIC
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BOB%
My S-10 blazer won't start in damp or rainy weather but starts right up on sunny or dry days. Could it be the spark plugs or the ignition module under the distributor cap?
May 26, 2025 at 9:00 AM
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STRAILER
  • ✓ASE Certified Mechanic
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  • ASE Certified Mechanic
Yep, moisture can cause the ignition system to fail if the distributor cap/rotor and plug wires get wet, when it is cold I would check for spark, this video will show you how:

https://www.youtube.com/watch?v=lXLJbuAZ4CE&t

This could be the engine coolant sensor not giving the correct reading when it is cold as well, you can check this by scanning the computer and checking the sensor value, here is the location of the sensor in case you need to swap it out.

https://www.youtube.com/watch?v=g4wRRxgjp94

Please go over these guides and get back to us.
May 26, 2025 at 5:34 PM
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