Suspected Air Regulator Issue, Confirmation??

[ghost_22_47]

The issue I am having is my idle like many other have had from research. However, I have been through the Service Manual and I am still at a loss.
Here is the issue
My idle after many adjustments and checks sits at the 1080 area if I disconnect or connect the AAC makes no difference at all.
-I have adjusted the AAC idle screw to no change at all
-Checked the connector wires for correct voltage and resistance to find no issue
-Removed the AAC, cleaned it, checked that the solinoid works by giving power and ground, and re-installed it with a new gasket, with no change.
-Adjusted my throttle plates to ensure they are in the proper closed position
-Checked the TPS for proper voltage
-Checked and re-timed to 20*
-Sprayed with Throttle Body Cleaner to check for leaks (nothing)
-I have Nistune and have run an active test on the AAC and still no change and reads 2% always because it is idleing so high with out the AAC being used it just stays there at 2%
-Car does run Rich (13 at times turing idle) so my guess is that the ECU is actually seeing extra air from somewhere
-Checked for boost leaks and no issues and boosts fine at 14.5psi

My next guess would be to attack the Air Regulator, thinking it may be stuck. I am a BMW Technician so I'm not some backyard mechanic and this is driving me nuts.

Anyone have any other ideas or agree I should just check out the Air Reg?

[narface]

If your throttle bodies are damaged, that can leak air. Otherwise, it is likely to be a faulty air regulator.

I used to have a high idle (1400rpm) and found out it was a faulty air regulator. I'm now using a refurbished air regulator and it fixed the problem. Of course, while I had everything on the intake side taken out, I took the chance to replace the throttle bodies. When I shine a flashlight behind the old throttle bodies, light seeped through the edges. I also replaced all the intake side gaskets. I used Nismo GT intake gaskets and Tomei intake manifold gasket. My engine now idles at 950rpm.

[GTR-Dad]

An intake leak would actually run lean on vac and rich on boost. Although you _should_ be able to adjust idle to factory spec, if it's
smooth at 1080, you're better than most.
I feel for you though. As good tech, it'd be frustrating to see a problem every time you fire up the car. :/

I'd check throttle sync before swapping out the AAC, but if you're sure there are no leaks that'd be a likely suspect.

The throttle blade seals are sometimes a leak source. (The elastormeric elements on the pivot) It doesn't take much to leak more than the AAC can accommodate and on boost you probably wouldn't miss the mass that would cause a 100 rpm idle elevation.

Dan

[bobbo]

I was told you can have air leaking by your recirc valves causing a high idle.

[ghost_22_47]

Thanks guys, I think I'll try pulling the Air Reg and seeing if it's stuck and either replace it or try and see if I can repair it by pulling the 4 screws out and checking the sweeping arm for binding.

Also going to smoke test it to make sure I dont have any pin hole leaks in any of the hoses.