Mark P

We started up another S4, and if you put your ear in that area you can just barely hear a similar sound, but mine you can hear from 25 feet away. I pressed against the various hoses in that area as well as the N75 and similar valves in that area. I couldn't hear any change in sound so I don't think I touched the area where a cracked hose is or anything. Maybe one of these valves failed interally? Something else in that area? I did notice that 2nd gear seemed to spike higher than normal, but then again I don't normally watch 2nd gear boost (normally I'm watching 3rd-6th). The car seems a bit sluggish as well (that's what caused me to look at the gauge). No CE light, but I haven't checked for any DTCs.

Does this sound like any common failure?

<img src="http://ctny.audiworld.com/mark/s4/parts/dsc05158.jpg">

AntiSocial

Spray WD-40 in that area, you should see bubbles where you're pulling vacuum. Check for a torn intake boot also.

J.Moss@TorqueFactory

be at atmospheric (sp?) pressure.

Jeff

AntiSocial

and you're not. =)

Mark P

or is there a hose connection right there that might be the culpret?

I checked for DTCs and there were none. I logged 3rd gear and haven't graphed it yet.

J.Moss@TorqueFactory

check every hose. Not too hard... The dealer and most bigger shops use a "Smoke Machine" to look for leaks.
Unfortuneately a pressure test will not show anything here as the area is after the throttle plate.
For the N75/wastegate hoses, you should be able to individually presurize them to check for leaks.

G-luck Mark P

Jeff

Mark P

As I was explaining this to someone else, I realized that you meant those other vacuum/boost valves. duh. Thanks, I'll see what I can find.