tiTTS

Ok, this has been happening for a while now and I cant figure out what is causing it. When I am driving then stop at a light, I hear a low "knock" sound coming from under the car almost sounds like a low volume backfire. The sound is usually rythmic and comes 4 in a row with about three seconds delay inbetween then goes away. It almost sounds like someone is knocking on my muffler. At first i thought it might be the gas sloshing around in the tank but ruled that out because it doesnt happen all of the time. It only happens when i am stopped. Anyone know what this is?

JohnLZ7W

Legend has it the quattro cars have a split fuel tank and every now and then if you listen carefully you can hear a pump transferring fuel from one side to the other. Sounds like a low thumping sound from a horror flic.

tiTTS

Yes, thats a good way to describe it.... is that a problem or normal??

JohnLZ7W

Lots of folks have it, probably everyone. Some people write it off as thermal expansion of the exhaust but really it's an imp in the gas tank using a bucket to keep everything on the level.

MCPaudiTT - DEFCON 1

<center><img src="http://www.archangelcastle.com/h3erathia/imp.jpg"></center><p>

[KRAFTIG]

Ha ha LOL!

OldSchool AG

&lt;Alex Trebek&gt;No, sorry&lt;/Alex Trebek&gt;

AudiTTboi

hey old school AG can u email me at hilfiger8703@yahoo.com ?? i need some help with my clutch and heard your knowledgeable about them thanks

TTBella

Maybe not, but that sure sounded good..lol.

macc4s

My wife and I both can hear this, coming from the back, rhythmic low bump/tap. Mine does it many times, not just 3 or 4. I don't have to be stopped, I can hear it slow rolling,too. WTF?!