Today I was severely bored and wanted to do something fun. I turned my system up really loud and noticed everything rattled outside the car. So I decided to fix it. First Job I took out my rear brake light fixture by removing the plastic rear interior and those plastic wing nuts. There was that carpet-like material that looks like shredded clothing on the backside of it. I noted that. I cut out 10 squares of it about an inch by an inch wide and poked a small X in the center of each one. I put them on the bolts, between the plastic of the light fixture and the metal of the back of the car and tightened them down from the inside. This only took about 20 minutes (I had to remove and clean stuff too, and find my scissors). Second Job My license plate rattled so bad it made the music sound like crap INSIDE the car! So I cut up some soft foam, almost like a couch cushion, and glued it to the four corners on the inside of the license plate. I have a license plate lens cover, and that vibrated too. So I glued a styrofoam peanut on each corner. The rattling virtually stopped and no foam is visible. Estimated time to fix: 5-10 minutes Third Job Foam baffles in the door jam make bass sound like crap. This was the easiest fix, but sucked becuase I lost a screw Remove the baffles from the jam. They have a screw at the top and slide out and up. I put electrical tape all over the back side of them (after wiping the dirt off) and taped around the edges good. Put them back in how they were before. Estimated time: 5 minutes Fourth Job This was by far the worst job. I used styrofoam peanuts. The screws kept falling out of the peanuts and I lost a few. You should use rubber washers to make it easier on yourself... Well anyway remove your 6x9 speakers (rear ones) from the fixture. While they're out, you should take the time to spray some sound deadener inside there, or put an XTC Foam 6x9 Baffle in it, for better sound quality. Put the rubber washers on the backside of the 6x9 and screw them down. After doing those four jobs, I have greatly reduced external noise. But I still have bad rattling. And that rattling is coming from my spoiler. I tightened it down as best I could but without luck, it still vibrates. You'll definitely notice a big difference in sound quality, both inside and out. I recommend taking one hour and doing these things. It was well worth the effort, and it was free too! Should I make a tech article of this? NOTE: I am extremely dirty! ------------------ 1992 Pontiac Firebird (stock) - 305ci V8 TBI / Automatic Trans / Every option, excluding leather - Killer car audio system: Aiwa CDC-MP3 head unit Rockford Fosgate 360a2 amp pair of 12" MTX Thunder 5000s in a custom box Pioneer 3-way 6x9s, soon to add more more more!

I found it alot easier to just spray rubberized under coating on any plastic to metal contacting spots. Less time consuming and $2.50 a can.

Thats messy and no fun.

when i decided to redo my system, i decided to do it all right..well i thought i was doing it right. the first thing i did was take out all my interior trim panels. while everything was out, i decided to spray 11 layers of rubber undercoasting on everything metal. when i did this i really noticed that when you tap on the panels from the outside, they are alot more stiff, and they dont have that "tinny" sound to them when thge stero is on. i also decided to go purchase 24 square feet of 1/2" carpet underlay and i put it from just about the hole from the 6x9 all the way back and around everything. i also decided that since all my trim panels were off, i got 18 square feet of underlay and put it on the back of all my panels. btw, i also took out the spare tire and all that ish - if your worried, get a can of that inflate a tire stuff. where there are areas of contact between two rattling pieces, put a little silicone on both surfaces, wait until it cures than put it back together. it took me alot of hours to do all this, but with 11 layers of rubber, and 42 square feet of underlay, sounds alot better, but there are still rattles :\