1999 ZR2 great truck, one problem, if it rains it won't start. No problems starting ever in any environment, add a bit of rain and forget about it guaranteed no start.

Any plausible ideas?

 

does it crank but not fire? Im guessing something in the engine electrical is getting wet either plug wire ends or distributor or such.

 

Yeah cranks just fine, my thinking is perhaps a bad distributor cap. What I was hoping for is someone that had a similar problem before I start replacing everything

 

Check your distributor cap it may be cracke, I had the same problem in my 97. I took me about 2 months to figure out that there was a small crack in the cap and allowing water in and getting the rotor wet.

 

Yah look at the cap and rotor my cap didnt make any noise but when I had it off there was definete burns on the distributor prongs and the rotor button had a burn through on the side of the electrode where it arched from the side not the point.