Random multiple cylinder misfire when wet/damp outside
 

Hi guys my truck has been having some engine misfire problems lately.
Truck is a 1998 Chevy 1500 4.3 V6 5 speed manual.

When ever the weather is wet or damp outside the truck jerks really bad at cruising speeds.
It seems to smooth out if I stomp on the gas.
Getting a code for random multiple cylinder misfire.

I have checked the dis cap and it seemed fine.

Any help would be great thanks ahead.

Re: Random multiple cylinder misfire when wet/damp outside
 

With mine it was the distributor cap.

Re: Random multiple cylinder misfire when wet/damp outside
 

How old are the plug wires?

Re: Random multiple cylinder misfire when wet/damp outside
 

Something like 2 years old

Re: Random multiple cylinder misfire when wet/damp outside
 

So I swapped out the dis cap with an old one that came off my Dads van.
The truck ran better for a few days and then started doing pretty much the same thing as before.
This being said, when the truck isn't jerking/misfiring it seems to run better with this cap then my other one, so pretty sure there's something wrong with my other cap maybe this one too.

So anyway I went ahead and ordered new plugs,wires,cap and Rotor. should be hear within the coming week.

Re: Random multiple cylinder misfire when wet/damp outside
 

Did they do the same thing with the 4.3 that they did with the V8s and try to have conductors crisscross the cap so that spark plug wires all came off the cap on the same side of the engine where the plugs are? If so, those caps are really problematic for the V8s, and there is a thread on here somewhere for that.

Re: Random multiple cylinder misfire when wet/damp outside
 

Yes they did the same thing.
Yeah I have read stores on this forum and others about these caps. Mostly quality issues
From caps failing in short periods time to them being bad new out of the box.

Re: Random multiple cylinder misfire when wet/damp outside
 

Put on the new cap and rotor today. The truck is running way better.
I'll give it a few days of driving to work and back before I call it a for sure win.:lol:

Re: Random multiple cylinder misfire when wet/damp outside
 

That was definitely a solution in search of a problem. They found one...:lol: