Engine stutters and then stalls after driving in heavy rain

[marco0782]

I've had this problem with my 98 240SX for a while now, since I had around 70k miles and now I have 125k. When I've been driving in heavy rain at highway speeds, eventually my car will begin to stutter (the RPMs drop and then shoot back up) and eventually I lose speed, and when it gets slow enough the car shuts off. Obviously this is a very dangerous situation to be in, but I would like to be able to drive my car when it rains.

Any ideas?

[marco0782]

I should also mention that I popped the hood to see if there was a lot of water in the engine bay, and from the top everything looked completely dry.

[s13redtaz]

what kind on intake do you have? stock or cold air/short ram etc...?

[skydragoness]

From a story I heard about a friend's Honda Accord that did the same thing it turned out to be a completely corroded distributor cap/rotor and corroded plug wires that were exposed to the elements. Take those off and inspect them. Look for white/green powder. Clean them w/ electrical contact cleaner (CRC--makes a good one) and a toothbrush. Let it all dry before turning on the car!!

Clean your MAF with the spray too (no toothbrush! the MAF element in the intake is delicate, it just needs a light spray), spray the plug going to the MAF, and just about all electrical contacts as well.

IMO, i think it's a good idea to start adding dry-gas (like Stabil or ISOheet) to your tank about once a month (maybe more so in the winter and wet months like spring). Replace your fuel filter if you haven't done so in a while.

Try those routes out.

[Zion8561]

Might also want to check the condition/tension of your belts (Alternator). Never had this problem on my 240, but my other car would have the same problem in heavy rain ended up being a slightly loose alternator belt that would slip when it got a lot of water on it which caused the car to bog down some. It is worth a try if you tried what was said ^up there^ and you are still having problems.

Edit: I never had my car bog down so much that it actually stalled, but still worth a look.