I have a new 09 LX Coupe (Canada) that I got about a month ago, and two weeks into having it, it developed an intermittent interior rattling. At first I thought it was coming from the passenger footwell, but recently I have pinpointed the source with complete confidence as from under the passenger seat.
Symptoms:
-rattling sound from passenger side near the floor
-rattling sound only when in motion, when passenger seat is unoccupied
-when passenger seat is occupied, rattle disappears
-rattling more prominent when over bumpy roads or higher speeds
-punching/shaking/agitating the passenger seat reproduces rattle
Resolution:
-Tighten (HARD) the two big bolts, with a 14mm socket wrench, that attach the seat directly into the floor. The bolts are each located on the left rear and right rear of the passenger seat. They are each covered with a plastic dust cap which can easily be popped off to access the bolts.
Now it might not make sense for a loose bolt to cause rattling; however, when I think back to my bicycle mechanic days, I was always amazed at how loose bolts (and other things that didn't look like they could physically rattle) could create a rattling sound.
After doing this, I have noticed that the rattle is now gone! However, I have yet to test this fix out on the highways. So give it a try and see if it works. From reading previous posts on this issue, this has worked for others. Good luck!
Symptoms:
-rattling sound from passenger side near the floor
-rattling sound only when in motion, when passenger seat is unoccupied
-when passenger seat is occupied, rattle disappears
-rattling more prominent when over bumpy roads or higher speeds
-punching/shaking/agitating the passenger seat reproduces rattle
Resolution:
-Tighten (HARD) the two big bolts, with a 14mm socket wrench, that attach the seat directly into the floor. The bolts are each located on the left rear and right rear of the passenger seat. They are each covered with a plastic dust cap which can easily be popped off to access the bolts.
Now it might not make sense for a loose bolt to cause rattling; however, when I think back to my bicycle mechanic days, I was always amazed at how loose bolts (and other things that didn't look like they could physically rattle) could create a rattling sound.
After doing this, I have noticed that the rattle is now gone! However, I have yet to test this fix out on the highways. So give it a try and see if it works. From reading previous posts on this issue, this has worked for others. Good luck!