Please forgive me if this has been posted before but I've done some fairly extensive searches and wasn't able to locate a duplicate problem.

I recently had my mechanic upgrade my turbos. I sent them to Blouch Turbo and they put in 997TT compressor wheels in my KO4 turbos for my 2001 S4. I got it back a few days ago and there's a pretty annoying high pitch whistle that seems to be associated with the turbos.

In my searches everyone keeps asking "Are you sure that's not how they're supposed to sound?" Yes, I'm sure. It's a very loud whistle that can be heard from both inside and outside the car. Around the RPMs that I would normally hear the turbos spool before I hear this whistling sound. The turbos still spool up but I'm not sure how much if any boost I'm losing since I don't have a boost gauge.

I've checked the hoses going in an out of the intercoolers and they seem to be on there pretty tight.

Any idea what it could be?

Thanks!

 

what kind of intake do you have?

What kind of boost are you making when you hear the sound? What RPMS?

Increased volumes of air over or through a different opening could be making your car into a musical instrument, basically a type of resonance.

 

I'm not sure what type of intakes there. Please forgive my ignorance. Could you give me some examples?

When I hear the whistling it's usually around 2,000 - 3,500 RPM. Before this is usually when I heard the turbos spool before (based on how hard the gas was pushed). So, I can still release the gas at 3,500 and the whistle will subside, which is why I think this is linked to the turbos somehow.

 

You might have a possible boost leak that is causing the pressured air to run over a surface causing a whistle. Run a boost leak test http://www.awe-tuning.com/media/pdf/...ure_tester.pdf - this is the write up to make the tester and perform it courtesy of AWE.

 

I'll see if I can get that created. Attached you'll find a video I made this morning that allows you to hear what I hear. This is with the window down but you can hear it in the cabin with the window up just the same, my camera just couldn't catch it.

Video: http://www.i9technologies.com/MOV00743.MPG

Can someone verify that it atleast sounds like a boost leak?

Thanks!

 

That sounds awesome haha! Are you sure he didnt install two turbine engines?? Do you notice any loss of power?

 

Haha.. That's funny

It's hard to tell with the loss of power because I installed an ECS Stage III clutch and LWFW and I'm still breaking it in. Don't get me wrong, there's plenty of power so far without flooring it. Just hard to gauge with any real metric.

 

We can tell the cars not warmed up yet

That sounds strange, call blouch and ask about it if you havent allready. Pressure testing wouldnt hurt...

 

It's warmed up. The coolant sensor is busted. Getting fixed today. Notice the oil temp, around 200.

I just called Blouch. He says that the turbos should make more sound but internal. My whistle is definitely external from some kind of air leaking.

Still investigating. I purchased all of the parts to test the intake pressure. I'm trying to make sure I test by the end of today.

Could this sound come from the DVs? I have 710Ns.

 

It might but highly doubt bc they only make a weird sound when you let of the gas in boost. Make sure you only have the pressure on the regulator at 15 psi or **** is going to be flying