Charge Pressure Control: Positive Deviation

[C9CRM]

Morning Gentlemen

Long time no post!! The S4 has been laying dormant in my garden for the summer with only the monthly 30 mile warm up run to check it still works. All has been fine until yesterday.

I warmed her up nicely then gave it a boot full on the A20 slip road (off the M25 roundabout) pulled nicely for about 5 seconds boost was showing 16 psi on the gauge then suddenly dropped to 5 psi and backed off.
I poodled down the A20 back home to get the laptop out. Tried the gas a few times briefly on the way back but 5 psi was the max.

Plugged in Vag com and had

1 Fault Found:
17965 - Charge Pressure Control: Positive Deviation
P1557 - 35-00

I reset the code took her round the block and same again, nice load of boost then straight into limp mode.

Searched through a couple of posts on here which would indicate TBB or F-hose.

Its had new MAF and 2 new N75's and 2 new 710N's within the last year.

Anyone else had the same and is it likely to be as simple as a new TBB?

Cheers

Chris

[C9CRM]

Ok, it was the TBB!! Split down the side



Put on the silicone one I had in the garage and back to normal again. 237.9 g/s MAF reading at 6320 RPM with peak boost at 2260 mbar actual at 3400 RPM

Cheers

Chris