Misses When Humid?

hey there my 2001 4x4 4.3 blazer will miss if its real muggy out. did a full tune up (cap,roter,plugs, and wires). still does it? and ideas? thanks much

Spray down the coil with water and see if it arcs

hey there my 2001 4x4 4.3 blazer will miss if its real muggy out. did a full tune up (cap,roter,plugs, and wires). still does it? and ideas? thanks much

What cap did you buy? If you didn't get an OEM cap, you may be just reinstalling a problem. I've found that Autozone/Advance Auto/O'Reilly/Napa (even Gold) caps are not a suitable replacement. I've only done a full tune on my blazer 2 times. The first time was Autozone crap. The second time was only a week after the first time - with an OEM cap and rotor. I was having exactly the same trouble as you state. My Blazer is a 2000 - I'm over 5 years on the tune-up, and just had to replace cap/rotor this spring. Food for thought. Also, make sure there is no moisture under the cap.


If you have the chance, and it's doing it when it's dark outside - pop the hood (disconnect the hood lamp) and look for arcing. If you see arcing, then you found your problem.

this is my 3rd cap/rotor (original,1 from advance auto parts, and 1 from Napa) still having the problem i will do what you said and re-post thanks much

Yep. Napa's caps are garbage. I had one in a truck that only lasted about 2 weeks and started arcing through the cap. That was real nice - in the middle of a blizzard.