I bought my 06 TL Auto /Nav about 3 months ago, with 4000 miles and still with it's factory oil. While I do enjoy driving my car, one thing I seen to notice is a small hissing (kinda like a spinning wheel scratching a needle) noise whenever I am driving in low speed (0 - 20 mph) and especially when the car is still cold. Is this normal and I am just parenoid or is there a problem with the car? Thanks

 

Or may be it's hissing form intake. Do you have your windows closed or open? If closed then I doubt if you can hear the intake at low speed.

 

All the windows are close, and it only occur when I push on the accelerator, so if I were to let go of the accelerator, the hissing stops. Should I be worried?

 

Avenger, check your filter cover might be not properly covered. If it is I'll say bring your can in and have it checked.

 

I "second" the post above. I remember reading a post sometime ago about someone's TL came from the factory with the air intake not connected to the throttle body. He had been sucking dirty air into his new car since Day 1, and the dealer refused to exchange his car for another new one. The problem was discovered during the first oil change if I remember right. So, after approx 5,000 miles of sucking dirty air, he was one sad TL owner.

SHORT ANSWER = Get it to the dealer ASAP in case your are sucking dirt.