Elthesh

iTrader: (1)

I have an issue with my AC. When driving around town the water drains fine, but when taking a highway trip, a vacuum is created inside the box holding all the water in. You begin to notice less and less airflow from the vents until there is almost none. Now, if you stop the car with the AC on or turn off the AC while still driving, a torrent of water drains from the drain hole. Then you start over. Air works fine until the water builds up too much. There is NOTHING blocking the drain hole, inside or out. This has been an issue since I bought the car in 2010.

There is just some kind of vacuum building up that holds all the water in and I have no idea why. Any ideas what the heck is going on and how to fix it? It's fairly annoying.

01WS6/tamu

iTrader: (37)

There is a 90 degree rubber elbow installed on the drain outlet at the factory. They usually get old and fall off. When you drive down the highway road draft causes cavitation and prevents proper drainage. Go to dealer and buy a evap drain tube they are about 5-10 dollars.

Elthesh

iTrader: (1)

Thank you! That is likely exactly what the problem is. I didn't even know that existed, and it definitely is no longer on there now. I'll get one and report back the next time I do any lengthy highway driving.

01WS6/tamu

iTrader: (37)

88-98 fullsize chevy gmc trucks use the same elbow if for some reason they can't find it. 96 1500 1/2 ton 2wd with 350 if they want a application