There was a recent downpour the past week (about 9 days straight of rain) and as I was driving the other day, my exhaust would sputter like crazy until i gave it at least 4000 rpm. This has happened in the past when it has rained, but this time it was happening much more often. Does anyone know what's causing this?

 

u may be geting water in your distributor cap ive got a sheared screw on mine and had the same problem till i used some boat sealant crap

 

id say u got some water in ur muffler, check that out, bcuz thats the same thing thats happend to me..