Truck won't start after rain

[dannic]

94 gmc sierra

every time it rained, and was still damp outside, my truck would not start. Plenty of juice and would turn over just fine, but would not start. After it dried out awhile, then the truck would start as normal.

I drove through a small stream, about 6" deep and the truck quit on me, right in the middle. It was not that I got stuck, the engine just up and quite. I hauled it out and it started right up the next morning.

Went outside to start truck in the morning, nice and dry, and now the truck doesn't start at all. I popped the hood to see what I could see and out jumps a big gray squirrel. NO WONDER my truck wont start ... without my squirrel in there, who is going to turn the crankshaft?

Any Ideas on where to start and if these random events might have a connection somewhere?

Thanks,

[PeteA216]

Well aside from the squirrel, it sounds like something with the ignition system. Possibly: Ignition module, coil, bad distributor cap or rotor. Even horrible wires, specifically the wire connecting the coil and distributor cap could be a culprit. It also sounds like it could be a failing fuel pump relay (found under the junction panel cover, on the passenger side firewall under the hood)

While cranking, check for spark and fuel. No fuel from the injectors: fuel pump relay... no spark: something ignition related.

[2000CAYukon]

The ground wire for the fuel pump is on the frame rail under the driver's seat. Make sure it is clean and tight. Perhaps it is getting wet and causing the fuel pump not to work.

//2000CAYukon

[JIMS59VETTE]

I had the exact same problem with my 96' 5.7L. I also suspected ignition sys. but it ended up being the fuel pump. I went with an AC-Delco pump as recommended by other postings and it started right up and has never failed to start since.