starting issues when the weather is humid?

1997 TOYOTA RAV4
200,000 MILES • 4 CYL • 4WD • AUTOMATIC
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AL FRANKLIN
As old as the car is, it runs well. There are no service lights on, and it passed state inspection a couple of months ago. But when it rains (or is particularly humid) it won't start. In dry weather it starts right up and has absolutely no problem. But in or after a rain it just turns over and over but won't catch - won't start. My garage (and mechanics) can't figure it out. Any advice?
Nov 16, 2024 at 4:38 PM
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JACOBANDNICKOLAS
  • ✓ASE Certified Mechanic
  • 110,193 POSTS
  • ASE Certified Mechanic
Hi,

How long has it been since the vehicle was tuned with a new distributor cap, rotor, plug wires, and plugs? I ask because if moisture enters the distributor, it can prevent it from getting ignition spark. I attached a pic below of the cap/wires that I'm referring to.

Also, if it won't start, either ignition spark or fuel is not present. My guess at this point is ignition spark is missing. Here is a link that explains how to check for ignition spark. Do this when it won't start.

https://www.2carpros.com/articles/how-to-check-for-ignition-spark

Let me know what has been done so far.

Take care,

Joe

See pic below.
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Nov 16, 2024 at 7:33 PM
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AL FRANKLIN
  • MEMBER
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Thanks Joe. Honestly, I can't imagine why my mechanics haven't looked into this very basic remedy. I'll talk with them tomorrow and get this old buggy back on the road. Thank you!
Nov 17, 2024 at 8:49 AM
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JACOBANDNICKOLAS
  • ✓ASE Certified Mechanic
  • 110,193 POSTS
  • ASE Certified Mechanic
Hi,

It's possible that he has considered it. However, anything is possible. If you can, let me know what he says or if you have other questions.

Take care,

Joe
Nov 17, 2024 at 8:11 PM
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