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Strange boost issues?

SomeAircraftMech

Passed Driver's Ed
Location
Fort Dix, NJ
Car(s)
2017 VW GTI S
Hey all, having some strange issues with boost recently, I'll start with this, car is 2017 GTI S, 64K miles, stage 2 EQT 93oct tune, IE intake, Baun FMIC, CTS DP, RS7 plugs, APR coils, Forge BOV, etc. Recently took a trip from NJ to FL and back car seemed fine except for getting stuck in Virginia snow on I95 for 7 hours. After getting back I noticed that boost gauge on the accessport at light cruise no load would read 2-3.5 psi, normally it sits about .5-.9 while cruising, but when the gas was pressed it would climb about 1 psi then drop as if it was dropping boost and does it consistently, it will build up just maintaining speed ON LEVEL HIGHWAY then drop off when gas is pressed and seems slower to build up when accelerating. Also on most any given day my peak boost is 28.8ish steadily, now the car struggles to make that even in the 10 degree F weather it wants to max out at 24ish psi, I managed to get 27 on one run but only on one run. I've pulled intake and downpipe and checked the turbo for play in the shaft or damage to the rotors and found none, inspected and tightened all boost couplings, I/C Piping, checked wastegate voltage was set properly, checked for play in the wastegate actuator rod, and BOV lines and rebuilt the BOV piston and seals. Found nothing out of the ordinary. was maybe thinking the boost control valve may be failing? Some sort of boost regulation issue? Any recommendations on what else to check? I'll post the datalog, its a bit shitty because I've not many places to run a decent one around here not to mention reads are shitty and icy. If its not decent enough let me know and ill try to run a better one.

https://datazap.me/u/fullspool/low-boost-jan-22?log=0&data=7-11
 

tigeo

Autocross Champion
Put the stock DV back in and give it a whirl.
 
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