I have a 1999 silverado Z71 extended cab that has within the last few months started pooling water under the driver's side floor board under the carpet. First off there is no coolant being lost and no antifreeze smell, no condensation on the windshield, the drain for the evaporator box has been checked and unclogged, also it is not pinched. I have pulled the carpet up and tried to find where the water was coming from and there is absolutely no way of telling where it is coming from. The only thing that I can figure is that the floor is extremely hot and the air running through the console to the back is extremely cold could cause condensation, but this is a lot of water to be condensation. I usually keep a sham wow under the carpet and just check it about every few days and wring it out, but I shouldn't have to do this. Also I bought this truck brand new. There is no water at all when it rains, unless the A/C is running. I have called several dealerships and small garages and no one can help me with this problem. They all say that I have tried everything that they would try and that they have never heard of or seen a problem like this. I hope that I can get the answer from you guys. Y'all seem to know your stuff on this forum. Thanks in advance for any help that can be rendered.

 

drain tube is probably pulled loose from the ac unit, the ac uniit does not set completly against the firewall If memory serves me corect, the drain tube fits into the ac box then exits through the firewall about 1/2 inch gap between them ???????? just a quick idea!

 

Hi steve wolfe,

Welcome to the Chevy Forums.

There's usually a small A/C drain tube going thru the passenger side firewall to drain condensation from your A/C unit.

Sometimes it clogs with a small amount of grit or dirt. Try a pipe cleaner, or a smaller piece of tubing to knock the obstruction free. Anything soft enough not to damage the line, but firm enough to break the mud loose.

 

Thanks for the input, but I have already run a hanger through the drain and unclogged it and it drains good now. This was done over a month ago and I still have the problem.

 

this was helpful my truck does the same thing on the passenger floor,