Ok guys...here's the situation. I had the strange rear deck rattle for the longest time now and after taking my car to Acura again and again with no resolution, I finally decided to tackle the issue myself. I thought i was having the dreaded 3rd brake light problem so I removed the seats, the c-pillar covers, the rear shelf, AND the 3rd brake light. Just to see if my guess was correct, I drove around with my 'stripped' back seat to see if the noise would be gone. Boy, was I wrong. I searched and searched for parts that could possibly move and make a sound but I found nothing. I couldn't reproduce the noise when the car was parked, so I had a friend drive me around while I hunted for the sound. Everytime we hit some rough pavement, I would hear the dreaded ticking sound. I could also see the bushing at the top of the strut compressing when the sound occurred. What could this be? Any of your ideas would help...i'm completely lost.

 

Did you remove the speakers as well? I only think of this as one of the grills on top of the speakers rattles with certain music, but not on rough pavement.

maybe the spare tire is moving or vibrating?

 

i can try that later, but the sound distinctly comes from that rear strut. shouldn't i be able to reproduce the speaker grille just by banging on it?

 

If you have a Navi, check the Navi mounts.

 

check the spot welds at the rear windshield around it. There will be two pieces of what looks like sheet metal and there spot welded around the whole glass like every 3 inches or so. Use a small flathead screwdriver and insert in the gap between them and twist lightlly to spread apart ever so slight. Do this at all the spot welds...I've seen it plenty of times on cl's and tl's!!