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post #1 of 1 (permalink) Old 04-10-2019, 02:30 PM Thread Starter
Join Date: Apr 2019
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Sound Absorber, Plenum Drain Valve, A/C Drain

I have a question about the drains under the windshield and the sound proofing that is on the firewall. I had water coming into the passenger side footwell. I googled the problem, and came up with the usual suggestions about the A/C drain. I put a 3 hose extension on the A/C drain, ran it through a car wash, and still got lots of water on the floor. Then I took off the cowl grille and checked the drains under the windshield. They were all clear.

I eventually realized that the problem was the seal around the A/C drain.

There are three drains under the grille cowl, one on each side and one in the center. The plenum drain in the center routes water UNDER the sound proofing that is against the firewall, so that it runs right over the A/C drain. When the seal is bad, the water runs into the passenger compartment.

Here is a link to the sound absorber and a diagram showing where it sits: https://www.wholesalegmpartsonline.c.../25841605.html

link to the plenum drain valve:

My question is this: why the heck is the center drain underneath the sound proofing, so that it literally pours water between the firewall and the sound proofing? I had to remove the sound proofing to fix the seal around the A/C drain. I ordered a new one and Im wondering if I should try cutting it so that the center drain puts the water outside of the absorber. But then Ill be dumping water onto the soft, fabric side of the absorber

rather than the reflective inner lining that faces the firewall.

The pictures are of the old sound absorber. It's torn where I had to tear off the bottom to access the A/C drain (before I decided to just take it off completely).

Any thoughts or ideas?
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