Intake flaps not functioning correctly

[bcornish]

Looking for any suggestions on why my car is holding the intake runner flaps open at low RPM. After a recent carbon clean I had codes P2004/5 pop up but then disappeared within a day or two, then the car has started opening the flaps to their high RPM state even when idling. On cold start ups this doesn't happen but once the coolant temp reaches 60C they open fully. They behave normally below this temp (0% below 4500rpm and 99% above it position wise) but won't change position above it. My understanding is they should always sit at 0% position below 4500rpm regardless of engine/coolant temp. The only other indicator I have noticed is slightly elevated idling RPM on start up (800rpm instead of the usual 600rpm) and higher EGT temps (730C while cruising compared to sub 650C before), which I am reading using a P3 gauge.

For context I drive a 2009 manual S5 with the plastic intake manifold and a JHM ECU tune. I have checked all vacuum lines for leaks as well as both vacuum solenoids on and under the intake manifold. The intake runner flaps can move freely when checked manually with a hand vacuum pump. I can also see the car reading the flap position correctly via VCDS, because when I disconnect a vacuum line to one of the runner sides its actual vs specified position changes and I get an error code (P2004/5 depending on which side I remove). I have also disconnected the battery to reset things like long term fuel trend etc to no avail. The only thing I have yet to do but is on the list as a possible fix is to re-flash the car again with the JHM tune to see if that sorts the issue. The car has been tuned for a 18 months or now without issue so struggle to think its the culprit.

https://imgur.com/a/qgYoFCW

Pic above is of the measuring blocks I am reading and the point when the flaps decide to open fully. I was wondering if there was some sort of adaptation to run to correct for this but after plenty of googling and searching forums I have yet to find anyone else experiencing this same issue. Thank you in advance for any advice or suggestions!

[mauromj]

Any luck? I am about to pull my manifold myself. I am hoping the solenoid valve is bad, or a vacuum line is compromised.

[jxyjimmy]

https://forums.ross-tech.com/index.php?threads/25830/
I found this on the ross tech forums. i haven't read through it all but it looks to be the same problem you're experiencing. Possibly a solution in here. best of luck!