Intermittent Low boost

[DDale]

Hi all,

Got a 2005 mk5 golf GTI with axx engine k03. I have been having an intermittent boost issue.

Issue
Sometimes the car wont boost past 15 psi and gradually lowers to 7psi, It also feels like it needed more throttle to reach peak.
Restarting the car fixes the problem 80% of the time. Sometimes it also fixes itself halfway of driving.
It happens more after filling up, switching fuel from 100 octane to 98 made it worse (issue happens throughout the whole tank).
Last time I filled up car ran fine throughout the whole tank, peaking 27psi and holding 23-25psi. Slight throttle pulls hard and reaches peak with ease.

Diagnosis
No CEL or error codes.
Did some logging for N75, Specified boost, and Actual Boost. Logs shows Specified boost is low compared to when car runs fine.
I don't think boost leak is an issue since actual boost actually matches the specified.
Green = car pulls fine
Red = boost issue


Mods:
Car is tuned with Unitronic Stage 2 HPFP
Intake
Catless DP
Upgraded HPFP
Rev D DV
CTS R8 Coil packs
CTS PCV Revamp

Recently replaced:
Spark Plugs
Cam follower
Cam chain & tensioner
n80 Purge Valve
Boost pipe O-rings

Anyone had the same issue?
Any input is welcome. Thank you in advance