I have a 2006 Jetta with 90,000 miles. There is a low level noise which my mechanic seems to think it is in the engine or transmission. From the drivers seat it seems to be on the passenger side of the car. The noise is there when the car is stopped or moving. It seems more pronounced when you you give the engine gas. I hear it at 1000 RPMs and above, although the mechanic can here it on the rack. The sound is a pulsating un un un. If you have ever heard a fountain pump when the water is to low to pump, it is a similar sound. The engine and the transmission seem to work normal.