OK, i have an 88 4runner 22re 4cylinder 5 sp. after letting the truck sit over night out in the rain. i start it up and the exhaust sounds different deeper than before and and it sputters. this is the first time this has happened in a long time. last time it sputtered while driving in the rain and would almost die. but i replaced the distributor cap and spark plugs and it fixed it. I drove it a short distance and i check my radiator reseriovr tank and it was almost bone dry so i added water to it. the reason this happens is because i have a slow radiator leak along the top seam. what would be causing it to do this?? how can it be fixed?? i have a factory service manual. also what is the pc valve and the maf??? thanks please reply steven

 

have you changed the rubber O-ring on the distributer? It acts as a gasket between the dist. cap and dist.

 

i believe so. see it wasnt doing it when i drove it home in the rain. it did it after it sat all night in the rain.

 

sounds like condensation build up in the distributor.
I would also check the PCV valve. If they get clogged they can cause problems too.
Also check the connections from the air box to the throttle body if there is a leak it could be coming from there.