Over the 4th of July weekend I took a road trip to St. Louis during which I noticed the carpet under my feet was getting wet from underneath. I thought it was pretty odd because I had the TSB for the leaking AC evaporator complied with and couldn't see any leaks anywhere else. I knew I was going to have to get under there and see what was going on, so I finally got my chance last week and pulled out the driver seat to lift the carpet. Well I found a half inch of water in my floor. That was great. So I stripped out the carpet to let it dry.



Looked for and found the leak on the evaporator, again.



It was so high up on the firewall that the water leaked behind the carpet, so I had no idea it was happening. It had probably been doing that for over a year. So I get to the shop and have that fixed, again. But now my carpet is soaked and is going to take a couple of days to dry. So I decided to use the opportunity to install sound insulation on the floor pan.



I looked at the well-known Dynomat stuff, but I picked this stuff instead:
Scosche Accumat Hyperflex

It comes in nice 2*2 sheets that are easy to use.



So some of the obvious points here are make sure the car is clean. I used a spray bottle and some isopropyl alcohol to clean off all the metal surfaces. I also pulled all of the wiring harnesses loose and detached the seat belts. Here's the back seat:



The way I did it was a sheet at a time. More on that later. I dropped a sheet into place and then used a razor to cut the corners and make a nice fit. Pretty basic really.



Then you peel the backing off and stick it on. Be careful not to let the adhesive stick to itself. That can be a pain. Now the real trick to this stuff is adhesion. It really doesn't matter which product you use. The more surface area that you get the adhesive to solidly attach to, the better. If the sheet is just laying on the metal but not stuck to it, it's useless. So, to get a really good stick, use a trim roller.



Get a good quality roller. I bought a cheap-O one thinking I was only going to use it this once and it broke after about 2 minutes. As you roll, you can see that the foil backing will tear a little. That's perfectly okay. In fact, expect it. If you get an air bubble, cut an "X" in the bubble and roll the air out. Get as much of the sheet to stick as you possibly can.

Now you are not going to get every spot covered. You don't need to actually, but the more the better. Save your scraps and stick them onto places they'll fit. Here's an example:



Now like I said, I did a "sheet at a time" method. If I was going to do this again, I would do a "section of the car at a time" method. It would make it easier to install many smaller pieces that fit well rather then trying to do a big sheet at once. Plus you won't get as many gaps like in the picture above.

I haven't driven it yet, so I don't know how much a difference it's going to make. I'll post again with a report.

 

I had water leaking into my floor board as well, there was a gap between the firewall and it allowed water to come right in. Might want to get it looked at by the dealer.
I like what you've done.

 

Gap in the firewall? Like where exactly? I'm not too worried, my leak was definitely from the AC, but it doesn't hurt to look.

Anyway, I just drove it. With everything off, ambient noise is slightly reduced. Road and tire noise was the biggest change, which makes sense. No change in engine or wind noise, which also makes sense.

The big difference is in the sound system. A huge difference actually. There are absolutely zero rattles or buzzes coming from anywhere. The sound is perfectly crisp. I used NIN Ringfinger to try it out and nothing was able to rattle. Basically put, its ******* tight.

 

Not sure where the gap was, driver side is all I know.

 

good write up

 

Nice.

I bet your fingers hurt like hell though from not wearing gloves.

 

What do you mean? There really was no problem with the material that required gloves.