Hello,
I'm still lookin' for the reason why my car doesn't run well (only 463ch with FVD tune, AWE Straight pipes, Forge DV with yellow springs. I think I would get 500 at least, isn't it?).
Actually, I can't get or keep my max boost pressure. I get 1.0b for a while then 0.8/0.9.
So I decided to check my boost system and, here is the video of it:


I can't hear not any leak, it's like if the leak is so huge that it doesn't make any sound, or maybe the leak is in recirculation so the air doesn't escape to exterior.
The systeme never gets any pressure, You can see on the mano 0.4b, but it's a problem with my mano that never fall down to 0. The real pressure is really 0b when I stop.
Does anybody would have any idea of what could be the problem, please?
Maybe a valve or something else???

 

i'll post this again in the hope it helps.

my most recent leak was a bad check valve that was up top of the plenum. i replaced all the check valves and n75 at the same time and the leak was gone. the plastic housing of the check valve in question was simply cracked and it whistled the minute we pressure tested from the first turbo.

i would change ALL those; the n75 as well as the two check valves, they are very inexpensive. i cannot advise any specifics related to the tester itself.

 

you need to put it to 20 psi and disconnect that hose... then hook up a separate gauge and check how fast it goes down... if it drops more then 3 psi in 20 seconds its leaking