Occasionally in my new A4 I hear a low tremor from the back of the car for a few seconds when I start the car (typically when the car is warm from an earlier drive). It almost sounds like a sucking noise. I am tempted to believe this might have to do with the fuel "equalizer" process (or someting similar) that I believe takes place on occasion. The noise lasts little and it then disappears. Has anyone noticed it too?

Frank

The gas tank is shaped like an upside down U. There is a fuel pump that keeps gas levels even on both sides. I often here it when first firing up the engine. Could be this.

GaryJ
30Vqms

GaryJ,
thanks for the insight. I think that you are right.
Frank