The heater box drain often gets blocked and the heater box fills with water. Large amounts of water can be trapped in there. I had so much water in there that the fan blade was hitting it. The mechanic who cleared the drain said severl quarts of water came out. The water comes from air conditioner evaporator and rain water that gets in throught the cabin air filter hole which is just below the passenger side windshield wiper blade. You have to take off a plastic piece to get to it. Would you believe that they did not install a cabin filter at the factory when this car was new? Cheap b _ _ _ _ _ _ s. I had to get one from NAPA and install it myself.

 

have you found a way to fix this issue yet?

 

I think I have the same problem. I thought that I had mold
running through the system, so I bought some disinfectant for the
system which I thought would solve the problem for about a week.
The smell came back. Do have any directions on how to drain the
the heater box and evaporator.

 

have either of you talked to a GM dealership to see if this might be a common issue which case they have a fix for it?

 

Yea, I did but they told me it would cost me for something I think I
can do myself. That's why I'm asking if there are directions.

 

The fix for the water in the heater box is simple. Just clear the drain which is on the firewall behind the passenger side front wheel. Hard to get to without removing the passenger side front wheel. I took it to a gas station that had a lift and they stuck a screwdriver in the drain and cleared it. The mechanic got all wet. They did not charge me any moneybut I gave them a ten dollar tip as he worked on it for 20 minutes. Put in a new cabin filter too as it might prevent some rain water from getting into the heater box. They did not put a cabin air filter in my car when it was new from the factory and I think that caused some of the water in the heater box along with condensation from the air conditioner evaporator.

 

Thanks for the info. I'll do that tomorrow. But I think i saw in
another forum that you need some kind of deflector so that rain water
does not go in where the filter is located. Have you heard about
that? Not sure myself. But again thanks for the info.[img]smileys/smiley1.gif[/img]

 

Yes, there should be a dirverter. A piece of plastic to keep rain water from getting in via the cabin filter hole. The main problem, however,isstill the drian clogging up. If the drain was not clogged up all this rain water would just enter the heater box and then go right go down the drain and not be a problem.

 

Thanks again for the info. Will try to call dealer tomorrow see how much it will cost.

 

Well tried doing it about three days ago (finally have a lil spare
time). But I can seem to find it. What I did was pour some
water down it maybe thats what you we're talking about not sure.
Anyway water did pure out the back end where you said it would
be. But not sure if that is it or some kind of drain. Where
the water came out it was the back of the wheel well where the stock
plasic ground effect meets the bottom of the weel well. Is that
it? Or am I missing it totally. I still have that musky
moldly smell in the a/c system. Tried the disinfectant that is
sold in many auto parts stores. Worked for about a week than the
smell came back. Maybe the previous owner put a cabin filter in
don't know. It's a 2000 Olds GX Not sure how to check. Anybody else have the
same problem? Any help would be great.
Edited by: lunasea808