Front Passenger Side Water Leak - Solved

paauto · April 11, 2020

Here's the summary. I had dampness in front passenger footwell. Sunroof drain tube grommet had pulled out of firewall and allowed water to enter cab along sidewall under the fuse panel. I was able to get the grommet back in place. The detail is below.

I was in the process of swapping the front passenger side kick panel/threshold out the other day (original was beaten up pretty badly) and when I pulled the carpet back I noticed the carpet pad was damp in the upper right part of the footwell. The foam-backed rubber pad that sits at a 45 degree angle toward the firewall was also wet on the right half of the underside.

I removed the lower glove box compartment and started tracing the water source up the side wall toward the corner where the A-pillar, sidewall and firewall converge behind the fuse panel. I removed the A-pillar cover/handle (remove the cover plugs, take out the two bolts and pull on the handle to release the metal clip at the top from the A-pillar). Everything in the A-pillar was dry, so the leak was somewhere below or at the window.

I needed to get a look at the bottom of the windshield from the inside. To do that I needed to remove the dash cover (the part that spans the full length of the front of the dashboard (nearest the window) and includes the speaker covers and has the light sensor in the middle). To remove this I also needed to remove the driver's side A-pillar cover/handle. I used a plastic trim tool to pry the seam of the cover up. There are ~10 metal clips on the underside of the cover that clip into slots in the dash. The best way is to start at the left speaker cover and move the tool to the right until you hit the next clip then rotate the tool to pop the clip out, then move right to the next one. Once the clips are freed, the panel should lift up. You then need to remove the connection to the sensor. Once the sensor is disconnected, the cover can be moved out of the way.

I was finally able to feed my endoscope down from the bottom inside of the right corner of the windshield and I could see the problem - the grommet on the drain tube from the sunroof had pulled out of the firewall, allowing rainwater to run down the sidewall.

I was able to use an angled trim tool from the top and a long screwdriver through the fuse panel access panel to push the grommet back in.

I let the carpet and pad dry out thoroughly and sprayed Clorox on the bottom of the carpet and the pad.

I must have caught this early because there was no mildew smell either before or after. I had the truck off road the morning I noticed the dampness. I had bounced it down over a berm accidentally and am thinking that maybe that jarred the grommet loose. Probably not properly installed when the truck was built.

Everything is back together.