Just bought a used 2003 A6 2.7T and now has 61,000 miles. Went to the store this morning and noticed a high pitched whine from the engine. Sounds like a siren shutting off when I turned the engine off. I've never had a car with a turbo before, does this sound like a turbo problem or is this a common sound with this car? Although I've had the car for 4 weeks and never heard it before. Ait temp this morning was high 30"s here, related? Thanks for any input.

 

Is it an automatic? Its probably the SAP pump, it turns on for a minute to pump air into the cat converters then turns off. Kinda sounds like a vaccum cleaner when they go bad.

 

Thnaks for taking the time to respond

 

I'm curious, whats the differance? I drive a manual with a SAP.

 

Not all manuals are equipped with SAP pumps, S4 2.7T's that have manuals have NO SAP pumps.

 

What does SAP mean?

 

If noise continues check your power steering.

 

I have a 2002 A6 3.0 Qattro, every time I shut the engine down I also hear a loud wining sound . I always thought it was the double cooling fans, To me it sounds awsome
You sound very knowelegable on prety much all Audi subjects, If you have any more info on theSAP , how it works when it works and so on that you could share it would be greatly appreacheted.... Thanks..

 

The SAP (secondary air pump) is a large plastic pump thats only used on cold starts to pump air into the cat converters to heat them up faster to aid in emmisions. Its only on for about a minute so chances are if your hearing something other than a cold start than its not the SAP pump. The SAP pumps generally get dirt in the bearing making them become really loud and they sound like a vaccum cleaner under the hood for about a minute then goes away, its doesn't affect performance in the least.
Now if you are hearing something powering down with the engine and has a whine its probably the electric fans turning off, they may also be getting dirt in the bearings causing them to escalate in noise volumn.
I doubt any of you are having turbo issues as these will sound like a police siren when under boost when they go bad.

 

Thanks , that helps me allot, itprobley saved me a ton of money the sound i hear may be my fans on the way out....I hate to bother you, or in any way use you as my personal service derictory but I have to ask one more question...Can I check my coils, out of the car and if so do you know how..
I am a general contractor and would be happy to help you in that area if possible....