Need Help Diagnosing Boost Issue


New member
I have a 2007 GTI currently running a Unitronic stg 2 tune. I have a forge diverter valve spacer, so normally when I let off the throttle I can hear blowoff. I started driving it a few days ago and the car felt super sluggish. About an hour later that I wasn't hearing any blowoff. I currently have no codes. I have some graphs below showing actual boost, specified boost, and n75 duty. This data is from a one mile drive around my block.

My first thought was boost leak. I stuck some PVC on my air intake and unscrewed the oil fill cap and pressurized to 15 PSI and I couldn't hear anything. The air slowly leaked mainly from the oil fill cap and my janky PCV rig dropping to about 10 PSI in 2 minutes. I repeated this while squirting soap all over my engine bay and I didn't see/hear anything. My next suspect was the diverter valve (rev c) so I yanked it and the connections had a fair amount of oil in them. The plungers and o-rings were perfectly intact so I just put it back in the car. Next I went for a drive a logged the above data.

I don't really know what to make of this. If we believe the 'actual_boost' number, then my car is not making any boost...?. Also, why is the specified boost so low? There's a blip on startup where it asks for 1400mbar, and then after that, throughout the whole rpm range specified boost is bounded from above by 800mbar. So why is my stg2 car requesting little boy levels of boost? The n75 % duty is down there in orange, it blips on startup and then maintains 0%.

Not really sure what I should do here. Next ill probably yank the n75 valve and see how it looks or something. Any advice would be appreciated fellas!