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Sound from rear of car

2564 Views 17 Replies 8 Participants Last post by  Dara
I 've had my 2011 for nearly 3 years and I know this sound is normal, but never really cared what it was until now. Usually within the first few minutes of my morning drive, there is a sound, sometimes two or three times which sounds as if you ran over a piece of rubber and it hits the wheel well. I always figured it may be something to do with the gas tank pressurization. Kind of like a low pitched thump or thud type noise. Pretty distinct noise, I'm sure any gen 1 owner will know the sound.
Anyway, what is it for sure???
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I suppose it could be what PH2 said. I never in a million years would have guessed that, so I am not positive that is where the noise is coming from. I know it is not bump related or anything like that. It usually occurs within the first half mile of driving. And if you have ever run over a small piece of rubber such as from a tire and it bounces off the inner wheel well, that is exactly what it sounds like. And I am positive that is not the cause. It is too "regular" of a noise to be something I run over. Sounds like it is coming from the right rear of the car. I will look at the spoiler as PH2 mentioned, but even if that is the cause, I assume it would not be something you would be able to notice just by looking at it. Anyway, keep the ideas coming. THANKS
The spoiler expanse sound is a "pop" sound like an acorn hit the back of the car. The gas tank pressurization system (in the right rear) is a more rhythmic sound, like a small buzzing/banging sound.
I hear this 'acorn' way too often. Is it normal to hear this almost every day?
Depends. Is the car experiencing enough if an external temperature change between night and day to force the spoiler's expansion/contraction? Perhaps your spoiler attachments are over-tightened, causing too much resistance to expansion movement, or maybe there is some dust/grit buildup interfering with the "sliding" action. Some dealers have removed the spoiler, cleaned, installed slip tape and snugged the attachment just enough but not too much.
I'd Be willing to bet good money that I can remove my spoiler and it will still make the same noise daily.
Seems like a good test to possibly eliminate one potential cause. Let us know how it goes.
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