RobC

The local Audi dealer had them for $33 each including tax. Took all of 15 minutes to replace them.

Definite seat of the pants improvement. Car pulls a little harder now, but more importantly doesn't give out at 5000 RPM and there seems to be more boost after shifting. Guess the real proof will be my next visit to the drag strip.

Haven't figured out yet whether there's an issue with the MAF. I'll continue to try to find another S4 that I can do some block 2 measurements on to see how I compare.

Couple other things...
1. I'm getting some clicking noises that I suspect to be the CV joints, but it doesn't seem to click as loudly as the bad CV joints in my Civic I had long ago. The clicking is louder when the wheel is turned, another sign of CV joint problems. Will the dealer deny warranty since I've got H&R coilovers?

2. While under the car investigating the clicking noise, I noticed that the driver's side turbo had just a little bit of oil on the housing. The passenger side turbo is dry as a bone. Is it K04 time or is this normal?

If it makes any difference for the above 2 questions, I've got 38K miles, CV joint boots look fine, the bushing that someone talked about the other day looks fine, there is no clicking noise when I rotate the wheel by hand while the car is jacked up, there is no turbo whine.

Ideas? Thoughts?