1999 Tahoe Problem When Humid or Raining

If it rains my truck will stall and not start until it dries. The plugs and wires are newer so I have ruled them out.
Is there a particular sensor that is sensitive to humid conditions that
may cause a stall/no start ?
Thanks
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What engine? Do you have a distributor or is this a DIS engine?
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Distributor 350 Engine
Cap & Rotor Were replaced recently. The problem was here before and after the new cap & rotor.
Thanks
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Fine..That removes one possibility, most likely. And, I believe you said that you had new spark plug cables as well...
I still suspect something in the ignition, but dont recall any sort of sensor that would be likely to be so humidity sensitive.
If you have the HEI ignition, I would pull the coil and check it carefully for arcing. I have seen this happen a number of times, and it can kill the ignition, some of or all of the time.
Can you replicate the situation with a mist bottle when there is no rain? If so, can you check your spark to plugs, maybe using a cheap spark gap plug tester, before and after misting around the engine compartment.
I know how frustrating this can be. And sometimes the trees obscure the forest.
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snipped-for-privacy@yahoo.com says...

Does your car have a distributor cap? That;'s another potetial source of the problem. You can also try buying a can of 'wire drier' at your local car parts store. When the car starts acting up, spray the part you think might be causing the problem. If the car starts, then you probably found the source fo the problem. -------------- Alex
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