ModifiedA4

if it was the summer, i'd put the A/C on and that <b>should</b> cause the A/C belt to slip more.

btw, this slipping noise only happens under heavy boost.

thanks!

Kris Hansen

Alternator would be my guess...

Silver Streakin'

how do you know it's a belt?

ModifiedA4

i really dont...but it sounds like a slipping belt.

ModifiedA4

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Kris Hansen

if you cut the wheel side to side, does it make the belt drag? what about every light, fan on hi, etc, does that make it drag? it's probably no the AC, since when the compressor is off, it more or less just freewheels.. Very slight resistance from the clutch.

The only problem I can see would be if the waterpump is starting to lock up..

If you say it's only under heavy boost, what would draw most on the system during these times? I was thinking alternator, just a guess.

ModifiedA4

i did the timing belt/waterpump 15k miles ago so I hope its not the water pump locking up.

it happens under heavy boost...i hear a belt screech and as the belt catches up to speed the screech diminishes and then stops.

No screech turning the wheel lock to lock.

Do you know if it possible to replace the accessory tensioner without replacing the belt?

BTW, I did the work on the timing belt ETC...so im to blame here

Silver Streakin'

I replaced that along with the acc belt tensioner when I did my TB-60k DIY service.

ModifiedA4

only to find its the A/C tensioner or viceversa