tapping engine on 05 a4 tdi

[ianhillls]

Hi all, this is my first post on here so go easy on me :Blush2:

I have just bought an 05 a4 s line tdi multitronic avant. well, i have noticed there is a tapping noise coming from the engine (didnt notice it when i bought it last week), which dissapears when the engine is reved.

It has covered 81k and had the cambelt and tensioner replaced 500 miles ago
the gearbox oil was changed at the same time.

the engine oil is fine.

has anyone got any ideas?

[ianhillls]

ok, ive just found out that when the air con is turned on, the noise dissapears.....

[blknight05]

hi iv got the same problem allthoe mines a manual,i havnt tried the aircon thoe,did you sort it out?

[toff]

It does sound like the sprung belt tensioner wheel might be the culprit.

I presume when the aircon pump pulley is pushed into the belt, the tensioner is under more pressure (the belt is pushing harder against it).

When I fitted a supercharger to my Golf a couple of years ago, I had a problem with the tensioner tapping - we took it out and made some adjustments (using the eccentric bolt) and it was quiet for ever more!

If the tensioner was replaced in the last 500 miles, it might need some adjustment.
Al.