I've got a 97 1500 w/ 5.2
The last couple rain storms I noticed when under light acceleration or just cruising on highway, the truck "bucks" for a brief moment. Tach does not move and there is no pattern to it. It's almost like a slight hessitation but it only occurs in rain. Cap is dry. Any ideas?

 

you have a cold air intake. maybe just alittle water getting in.

 

Take a look at the hood to cowl rubber seal mounted on the cowl. Mine comes loose or gets outta place about every other time I open the hood, letting water leak in if I don't reseat it. Could be plug wires, either needing replacement or rerouting. Pull the coil wire and see if there's corrosion in there.

 

Regular airbox but I did find that the seal on the cowl needs to be glued back in place. Thanks to the both of you for getting back to me. Kept looking at the inside of the cap and it was driving me nut because the inside was always dry. I'm going to glue the seal and get a new set of wires. Thanks again.