My 351W really despises rainy weather until it reaches normal operating temp. Anything I can check? It's a carbed HO engine with a K&N filter.

 

What is it doing? Rough idle or more? If it is idling rough check your choke setting. It might be off a little bit. Or check the TQ on your intake bolts and carb base. Also check the distributor cap for a crack. I was also just told to look to see if you are arcing across any wires under your hood.

 

Get a dark, damp rainy night and start your engine...make sure your truck is parked in a dark location...pop the hood and see if you see any arcing.

 

Figures I'd forget to mention the problem. Usually it will just stall out when you stop. If it doesn't when you stop, it will when you give it gas. Unless, you kinda pump it once and release as it starts to stall and then tap it a couple of more times before going.