Andrew MacLeod

recently bought a 2005 allroad, 110k miles, has a fairly new timing belt.

makes this noise at warm idle - sorry, may have to turn the volume up:

Allroads_Lead_Somewhere

It sounds like a pulley, or belt tensioner issue. Have you listened for the noise at say, 1500 RPM? At what point/rpm, does the noise go away?

Andrew MacLeod

Thanks for the post!

Seems most aggressive at and around idle. up around 1500 you can still hear it, but it's starting to blend in with engine noise. Around 2000 the engine runs smooth and the noise goes away.

5v/cyl

My A4 2.8l had a very similar sound that was most noticeable at idle and would go away as rpms increased. I traced it to the timing belt area, but not to the exact source of noise. I did a complete timing belt service and the noise was gone.

aartimus

Definitely serpentine belt tensioner bearing

awdjunkies

+1... Sounds like they skimped out on the entire job, and probably only did the belt and hopefully the WP & T-Stat.. For peace of mind, I would look at the records (If any), or pull it apart and do a complete job again...

Petethepug

When the tech got my timing belt kit it had all German OE parts. The tensioners in the kit were some kind of knock off part with factory part #'s. He did not install them and used factory VAG tensioners.