I've gone through the different threads dealing with the various leaks our Blazers seem prone to. Pulled my two rear drains and had washer fluid/water pour out because they were completely plugged. Should solve my cargo area dampness.
Now, my remaining problem is the passenger floorboard. I ran my AC and yes, I'm dripping condensate on the ground-good. However when I'm going down the highway I'm assuming it's being blown back onto the firewall and seeping in somehow. Whoever converted the AC from R-24 to 134a did a crappy job putting the who halves of the coil cover back together because the insulation is largely gone and I can feel cool air leaking around the seam. Is the drain an actual nipple drain or just a hole in the molding along the seam? It seems to be dripping fairly well-at least I hope. I noticed water trapped along the corner bottom of the door seal-right close to where the body transitions up to where the door hinges are. The bottom lip of the door was wet also-actually some rust where it's been getting trapped-right at the front edge. My question is where is this coming from? Is there another drain I'm not aware of? Last week we had very heavy rainfall and the one and only time I had the sunroof leak-along the front transition where the headliner joins the top of the windshield. Is it condensate or do I have trapped rainwater that's getting my passenger floorboard? If someone could point out what and where all the drains are that would be great-as well as any ideas why I'm getting water on my floorboard. Thanks!

 

JR, it always helps the forum if you give some info about your vehicle: year, model, 2 or 4 door, 2WD or 4WD, no. of miles, your location, and other pertinent data . A tip so you won't forget is to put the info in your signature, so it automatically appears each time you post.

 

Oppps....sorry. Got it fixed (my signature) that is.

 

Question: Why the heck is a picture of that bloody weep hole impossible to find on the internet? I spent a solid hour and pictures of a Dodge kept popping up...ugh.
Anyhow I just got back in from laying underneath my Blazer and looking yet again for that drain. I was able to locate a hole about 5/16" in diameter and shining a light on it I could see something like a filter/window screen mesh behind the hole. Is that it? If it is it's perfectly clean. I drove home from work today running the AC and my carpet passenger side is dry-so far.

 

Thanks for the info. On some GM sedans, there is a rubber hose to drain the condensation down to the pavement. Go to GM Parts Direct and look up some parts like a 'coil cover' or drain hose for a diagram of the part and help in finding it. I can't help you locate it other than that.

 

Some S-series trucks had a little hose sticking out of the bottom of the HVAC housing underhood right where it meets the firewall, but most do not. The hole is directly above the passenger side frame rail and is ~1/4" slot at the lowest point of the HVAC housing.

The reason why there really aren't pictures of it is because you cannot really see it with everything in there. If the passenger inner fender is pulled, you can get a better view. If you use a mechanics mirror, you should be able to see it, but lighting the area can be tricky as well giving how much stuff is packed in that area.

 

Thanks for the tips. Instead of a hole I'm looking for a 1/4" slot-is that correct? I think to eliminate any lingering doubts I'll go ahead and pull the inner fender. (I'd rather not-it looks like no small task with all the stuff crammed into that engine compartment.) I'm not sure what is bolted to the top of my reservoir but it looks like some type of transformer. Looks like there's a lot of stuff I'll have to remove in order to get to it. Honestly, I'd rather have a hose running down to keep condensate from leaking over the frame and firewall. I'm sure I could rig up something.
I did see a 'slot' of sorts a 1/4" wide and it was the lowest point on the cover. I also wonder if that 5/16" hole I saw once had a hose running out of it. If I'm seeing condensate running out around the seam and I hear a gurgling noise when I accelerate I guess that means my cover is full. My carpet has stayed dry so far. That must be it then. Mine is 18 years old and the plastic is literally crumbling in spots around the seam. I was thinking of squirting some insulation foam around the seam in order to seal it better. The silver insulation is gone-looks like it was torn when a PO had the AC serviced. What little was left was serving no purpose other than exploding into millions of pieces when I no more than breathed on it and it liked landing on my face.

 

This problem is annoying since I'm not sure what I'm looking for. My cover drains plenty of condensate-except it's dripping about mid-point on the seam where the two halves are bolted together. It's actually dripping onto the frame and then getting into the frame and dripping out further back. Whenever I park it after running it drips so much it actually leaves a puddle. Could it be blowing back onto the firewall and getting in somewhere there? I sprayed flex seal on and around the passenger floorboard plug just to eliminate that possibility. I have the gurgling noise behind the dash-indicating a heater core except I'm not smelling anti-freeze and I don't seem to be losing it either. Short of replacing the entire housing cover (is that possible to do without having to bleed the system?) I'm at wits end. I've even stuck an air nozzle underneath the entire housing hoping it might possibly clear out the drain.
Is there any type of opening for the HVAC system on that firewall that condensate might be getting in? Is there anything I can check behind the glovebox? Any and all help will be greatly appreciated!

 

Today I pulled the inner fender-and found the same hole I mentioned earlier that I'm seeing a screen behind. It's the only hole I'm seeing and it looks to be the lowest point on the cover where it meets the firewall.
Yesterday I got home after running the AC max with re-circulate (we've been having a heatwave for the last 2 miserable weeks) and I had a really wet floorboard when I got home. It was hot-should condensate be hot if it pools up?
I just thought of this-the baffle thingy, the thin foil insulation that went around the evaporator cover is gone. Could this be disrupting how and where it's supposed to drain? I'm grasping at straws here...

 

I finally found out what the problem was. It was indeed condensate leaking inside but my drain wasn't the issue. I pulled off the resistor? from the airbox cover and shined a flashlight inside. There was about 4 inches of leaves piled up against the coil. I bought one of those mechanic 3-prong grabby thingies and spent a good 20 minutes pulling out leaves and pine needles. That was 2 months ago and my floorboard has been dry ever since. Thanks for the replies and help everyone! Now, onto my burnt out HVAC/radio dashlights...