Water in the exhaust pipe? Totally normal.

Dear Car Talk

Dear Car Talk | Sep 01, 1993

Dear Tom and Ray:

I read your column every week, and consider you guys knowledgable experts. I'm hoping you guys can give me some insight on a problem before I pose it to my dealer. I've recently purchased a 1993 Dodge Pick Up with a 318 V8 engine. While idling, there is a great deal of water that is emitted from the exhaust pipe. It may be happening while I drive, too, but obviously, it's hard for me to determine. Is this a normal condition?

TOM: It's perfectly normal, Ed, and you shouldn't worry about it. If you remember your high school chemistry course, you may recall that when a hydrocarbon (like gasoline) burns completely, it produces nothing but carbon dioxide and plain old water. So the water coming out is a good sign. If nothing else, it tells you that your engine is running...which is more than my brother can say about HIS Dodge pick up.

RAY: It would be a problem if the water were NOT coming out the tailpipe, because that would mean it was staying inside and rotting the exhaust system. And incidentally, that's the way exhaust systems rot-- from the inside out.

TOM: By the way, if you're curious, and want to find out whether water is coming out while you're driving, too, you can always use my Patented Underbody Testing System (PUTS). I strap my brother to the exhaust system, and then drive around until he figures out what's going on under there. I'm not using him next weekend, so if you want him, I think he's available.

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