The Flapping and Slapping noise only occurs to the greatest extent when the car has sat in the sun for 30 minutes to an hour and the rear deck has gotten hot enough to expand and possibly warp. When the car is driven after getting sufficiently hot inside and you hit a bump or crack in the road the loose rear decking behind the power window shade moves with enough velocity to hit other stationary parts of the rear deck area. The noise is unacceptable in a $40,000 car.
The car has been dropped off four times over the past two years at the Toyota to try to locate the source of this noise. On the first two visits the car was not left outside in the direct hot sun to get the rear deck and interior hot enough to cause the decking to expand. On the third visit the technician though they found the source of the noise and added a couple of foam cushions to the underside of the rear deck just around the Cyclops light. This may have softened the noise but I suspect that the car was never put back in the full sun to fully test it.
Just this summer we had the occasion for my wife to ride in the back of the car and she pressed down on various areas of the decking behind the power shade. She found that the noise was 90% gone when the decking was held down. I added some foam above the Cyclops light and below it to isolate its movement. There was still a smaller amount of noise that I felt was coming from the corners of the rear decking and either the back window or the interior side molding on each side of the back window. I also added foam cushions squeezed between the window and the rear decking to isolate its free movement. The noise is completely gone with the addition of the foam in those three places. The dealer tried to adjust the rear deck panel behind the powered sun shade by adjusting the position and spacing.
In the end the dealer made the problem worse so it was present even when the car was not hot from the sun. I have put the foam pieces back on top of the rear panel at the corner of the windows and in the center of the Cyclops light and window. The sound is gone but Toyota never provided a fix.
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The Flapping and Slapping noise only occurs to the greatest extent when the car has sat in the sun for 30 minutes to an hour and the rear deck has gotten hot enough to expand and possibly warp. When the car is driven after getting sufficiently hot inside and you hit a bump or crack in the road the loose rear decking behind the power window shade moves with enough velocity to hit other stationary parts of the rear deck area. The noise is unacceptable in a $40,000 car.
The car has been dropped off four times over the past two years at the Toyota to try to locate the source of this noise. On the first two visits the car was not left outside in the direct hot sun to get the rear deck and interior hot enough to cause the decking to expand. On the third visit the technician though they found the source of the noise and added a couple of foam cushions to the underside of the rear deck just around the Cyclops light. This may have softened the noise but I suspect that the car was never put back in the full sun to fully test it.
Just this summer we had the occasion for my wife to ride in the back of the car and she pressed down on various areas of the decking behind the power shade. She found that the noise was 90% gone when the decking was held down. I added some foam above the Cyclops light and below it to isolate its movement. There was still a smaller amount of noise that I felt was coming from the corners of the rear decking and either the back window or the interior side molding on each side of the back window. I also added foam cushions squeezed between the window and the rear decking to isolate its free movement. The noise is completely gone with the addition of the foam in those three places. The dealer tried to adjust the rear deck panel behind the powered sun shade by adjusting the position and spacing.
In the end the dealer made the problem worse so it was present even when the car was not hot from the sun. I have put the foam pieces back on top of the rear panel at the corner of the windows and in the center of the Cyclops light and window. The sound is gone but Toyota never provided a fix.
- Craig J., St. Paul, MN, US