So the last couple thousand of miles Ive been driving my s4 i get a low whistle noise under really heavy acceleration. If i start off at 2000 rpm and ease all the way up to redline i wont ever hear the noise but whenever i punch it above......say 2500 rpm i get a low whistle noise coming from the engine bay, almost sounds as if it was in my heating/cooling system but i know thats not possible. Havnt noticed any big difference in performance but the noise does concern me seeing as replacing the turbos costs more than a years worth of grocerys. If i have the radio on even at low volume I cant really hear it just to give you an idea of how loud it is. Any ideas?

 

Are sure its not your turbos.... spooling?

 

Ive had the car since its had 68k on it and now it has 104k on it and the noise just started.....unless my turbos didnt decide to start spooling up until it hit 102k. They needed to be broken in.

 

get you codes checked and also pull the bed pan off and look for lose stuff or leeking stuff.

 

what size motor do you have? cus some audi motors have a whine that makes them sound supercharged even though they're not, i know mine did

 

The wine on the 4.2's is from the repositioning of the TB. They put it on the back of the block to save space.

 

I have a b5.

 

I assume you know what the normal turbo-spooling sounds? That being said, open the window and f you can drive next to a concrete barrier or something that the sound can resonate off of, be in second gear around 1500 rpm and gently increase RPM until you hear the turbos start to spool. Listen for any abnormal whine or noise.

 

After 23,000 miles I heard a whistle noise from the engine area. I thought it was a loose belt, but the Audi dealer found a fault in the crankcase vent valve and replaced the valve and hose under warranty.

 

I have that same exact problem, it is definitly not the turbos spooling up thats for shure, when he said low whislte noise he did not mean quiet whistle,he ment low tone whistle! I have yet to fix mine and now the car has absolutly no power whats so ever. I have 108k on mine and this just started out of the no where. I wil check that crankcase vent valve today and see if that is my same problem.

Does the car run extreamly rough with this problem or throw any codes because mine is throwing a random misfire 300 code. I changed the plugs and it still has the same problem checked the coil packs but did not notice a big diference. Is there any tell tell sign of if a specific coil pack is bad?