S3 , Turbo Noise, Normal ??

[Bainie]

Had my S3 for a few weeks now, and noticed when I lift off the throttle between 2.5/3k revs there is a whistle, like a toy dump valve . Guessing it is a recirc valve . Is it normal , or the start of something sinister ? Didn;t notice it to begin with , but I am a bit obsessed with noises ! 50k miles , facelift ...

 

[grainqey]

probably better with standard S3 owners replying but I've got a K04 on mine and it does make some funky noises compared to the K03 did but mines mapped as well to suit an AXX so boost build up will be different to a CDL engine

 

[S3Alex]

The diverter valve can make a few wheezing noises,and if remapped,the turbo can make quite a lot of whistling and screeching sounds,due to surge,but neither should cause significant problems unless the turbo is run to it's limits with a remap.

 

[Bainie]

Cheers guys , getting map soon , and warranty runs out in a few weeks so probably hearing every sound at the moment .. My old VXR s chattered more than whistled , and the mini didn't make any noise ...

 

[S3Alex]

Cheers guys , getting map soon , and warranty runs out in a few weeks so probably hearing every sound at the moment .. My old VXR s chattered more than whistled , and the mini didn't make any noise ...

Possibly....
Every car has it's own sounds,and every time something gets done to mine,a lot of those change,and it takes a while to get tuned in again to what's right and what's not.

My Cosworths snorted and chattered,the S3 was quiet until it's first and second maps,more so as the original turbo was pushed harder and harder.
Now the induction noise is virtually gone,with the huge turbo and ITG intake,there's no surge,and only the engine makes a lot of noise...

Generally,these are reliable and solid cars.

 

[Bainie]

Whistling on acceleration now as well as when I lift off , not sure if it is boosting less as well , or am I just getting used to the car . Going to get a local garage to have a look .

Does this sound like a boost leak somewhere ?

 

[grainqey]

I'd check the recirculating valve if you haven't already, it's pretty easy to get to with the K04's as its at the front of the engine at the top and see if there are any holes in it (it's easier to check if you take it apart-they just clip together on the plunger side)

HTH

 

[Bainie]

Cheers, I was reading a how 2 for that as you posted ! I think I will just replace that anyway , as it is cheaper than a diagnostics , and will do no harm being replaced