Need help pin pointing a leak (interior)

[itsnicyo]

I've been having an inside leak for sometime now and I'm ready to get to the bottom of it already. It's an 85 Monte SS and does not have T Tops. My passenger floor keeps getting wet, not puddling but wet. So I automatically assumed heater core and swapped that out last week only to have the same problem after I washed my car. Now I'm leaning towards a bad AC Box seal. I also feel heat coming from both sides of the under the dash after driving for sometime. Makes me think heat is creeping past the AC Box seal and getting into the vents, as the water is as well. I noticed the drip coming from where two plastic pieces meet for the vent. This is under the dash as well. What do you guys think??


Sent from my iPhone using Tapatalk

 

[Longroof79]

These cars can leak from any number of places... from a bad A/C heater box seal to bad pinch weld seams. I would start with the heater box. Have someone run a hose around the box while you're observing under the dash with your trusty flashlight.
Also make sure your drain is clear. Besides the body seams, other places could be run around the windshield frame( I know about that first hand). Another area I had a problem with, was the flapper seal in the lower portion of the air box. The rubber seal became compromised. I later replaced the flapper door and seal, but that's not usually the problem. I would focus on the air box seal.
Good luck!

 

[Clone TIE Pilot]

There are also two holes in the corners of the firewall that were poorly sealed by the factory. Only way to reach them is to pull both fenders off.

 

[pencero]

On an 82 I owned for a short time it was coming from somewhere right behind the heater box but since the heat worked just fine I cut up a small plastic bin a certain way and wedged it in there facing the other way so water would get diverted without pooling on the frame anymore. Not saying thats what you should do but this was on a daily driver car in not very good shape though. Laugh if you want to but it solved the problem for like $2 and I didn't feel like spending big bucks on the heat when it already was working fine regardless (once I knew it wasn't the water pump causing the problem*)

 

[itsnicyo]

Just ordered the box seal.. Hope this does it!


Sent from my iPhone using Tapatalk