Hello,

I've searched up and down the forum but I can't narrow down my problem to a specific answer, or set of answers..

We have a 2000 Blazer with the 4.3. If it rains or snows, or is otherwise moist outside, the thing will - not - start. I have narrowed it down to a spark/electrical issue.. but I wouldn't know where to start. The plugs and cap/rotor were replaced last summer/early fall. This problem did not start until this past winter (in other words, the truck has been 'rained on' with the new plugs/cap/rotor in) Not to rule any of them out, but I was looking for an answer to just pop up and someone to say "Oh ___ is common in these vehicles.."

Any ideas? Im thinking its definitely ignition related (we smell fuel when cranking..)

Thanks in advance,
Steve

 

Many no-start threads state to have your ignition system tested. Remove the ICM and coil and take them to your nearest autoparts store that has the appropriate testing equipment. Have both of these components tested repeatedly to get them hot as many faults only happen when the components are up to operating temperature.

Another thing worth looking into (and has been mentioned in the past) is the possibility of a clogged drain in the bottom of the distributor. This would allow moisture to accumulate in the distributor, affecting spark transfer.

Did you replace your wires at the same time? You only state plugs, cap, & rotor. The wires are just as much of a crucial component of the ignition system. You can check them at night with a small spray bottle of water. Mist down the wires as you have someone else try to start the engine. If you see the spark jumping out of the wires, you have found a problem.

Aside from ignition issues, it could be a fuel supply issue. Even though you smell fuel, it may not be the proper pressure or amount delivered. A fuel pressure test would tell you if you have problems with the system pressure while cranking and after you turn the key off. If the pressure drops after you turn the key off, the FPR is the likely cause.

As you can see, there is no magic bullet. No one can tell you "XX component is at fault, replace it and you will be good to go." You actually have to get your hands dirty and check things out. Well, that is unless you have a deep pocket... Remember, you are the one there with the vehicle and we could be thousands of miles away.

 

Gotcha.. I say it's not fuel because the vehicle works just fine when it's dry (and has had time to dry out..) which makes the distributor clog the most likely culprit, based on the fact that it runs like a champ when dry. I will also check out the wires, theyre cheap enough where if they werent replaced with the plugs, its worth doing anyway. Thanks for the help!