agant78

I have a 2000 Chevy Silverado, V-6 4.3L 94,000 miles that will not start when it's raining or very humid. Once it sits in the sun and dries out it will start right up no problems. I just need to know where to start looking for the problem, so i can get this fixed. I am in the military and I have to leave next week for awhile.

birdie

i had a problem such as yours and it was the coil- pack that was bad. i tested it by starting the truck and sprayed the coil with a mist of water from a spray bottle and i saw a spark come from the coil, meaning it was not water- tight which it sould be. it cost 50.00 to replace, easy to do

gfd749

first off, i would like to thank u for what u and your fellow soldiers do for all of us. secondly, i dont know how much help i can give u but maybe i can give u some ideas. have u checked your distributor cap or rotory button. i have had the problem with moisture getting under the distributor cap causing the 4.3 to MISS but i havent had or heard about the moisture causing it not to run. your distributor itself could be a little worn out. but before jumping into changing a distriubtor. try changing your distributor cap and rotory button and spray a thin coat of copper seal under your cap. the copper seal stopped mine from missing when it rained.

Thumper_ehhhhh

Tune up cap rotor and wires. Try spraying wd40 on the wires when your having problems. It wicks the moisture away. When it is running slide a screwdriver with a well insulated handle along the wires if you see arking or sparks wires are toast.

Tofutti

Sorry to dig up an old thread here, but, we have the same issue with a 2000 K1500 with a 4.3. If it's wet or has even been humid for a couple days, it turns over just fine, we can hear the fuel pump priming and all, but it won't fire. We've replaced cap and rotor, alternator (for a separate idle-surging issue), and lastly, the wires. When it's dry ( a couple days of high wind + sun + hood open) it will start before the engine even makes 2 full turns and runs/idles/drives PERFECTLY. As soon as the relative humidity hits about 60%, it's done. Will not start, or even try to.

We got it started and took a hose to it to try to troubleshoot it today. We sprayed everything under the hood with it idling, one electrical item at a time... (We never hit the coil or control module at all though) When we worked our way to the backside, as soon as the water hit the back of the new distributor cap it died quietly and instantly. There is a wire connector under the cap... Is that for the timing advance? and is/has there been an issue with that? Thoughts?
It'll be a few days before this thing will start again now....

We've also noticed that after it gets wet, the starter selenoid will not disengage, so when it starts (finally) the starter gets rolled along too. When it's dry the starter works and disengages normally. (Two separate issues, or one big wiring SNAFU?)
Thoughts?

mpsgtmo

I'm having the same problems with my S10. We have spark from the coil. Spark from the distributer. And a little gas. Nothing works.

wired1141

I had this same problem with a 92 5.7L and it was the coil wire.

KyN8

It's the distributer. Take off the cap and spray it with WD-40! It displaces the water and will be fine. My wife's car had the same problem and her dad told me about doin that and he is a mechanic. Never had another problem.

JeffBan

Has this years ago on an S10 I had. Replaced every component in the ignition system with no fix. I started chasing back the power wire from the distributor and found a big ball of green corrosion on it where the harness went along the firewall.

TJStemper

does my truck have this