Trouble making boost on LNF with ZFR

Hey all, I've been having some issues with my 2008 Chevy Cobalt SS/TC. My mods are below and a description of the situation.

AEM Cold Air Intake
ZZP Intercooler Piping
ZZP Intercooler
ZZP Catted Down-pipe
ZZP ZFR 6758

The car is HP Tuned, and has been running strong up until recently. I have been self tuning for over a year now with a lot of success. I just figured it wise I seek some advice before I went poking around my car aimlessly.

The turbo was making 24psi and the MAP was registering 255 for the DAL. However now the turbo is barely managing 14psi, and the DAL is only registering 196.

My STFT's are also falling very negative, and the cars exhaust has a lot of pops to it now when it didn't before.

The car seems to be running perfectly fine in every other aspect. I checked underneath the car and the exhaust manifold is completely intact and crack free; as is the turbo. I checked the oil and it looks fine, and the car is not smoking at all either.

Any ideas or advice would be greatly appreciated.

Blown intercooler or blew a charge pipe off. Wastegate failures and bov leaks all cause this issue

Quote:

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Originally Posted by cobaltssoverbooster

Blown intercooler or blew a charge pipe off. Wastegate failures and bov leaks all cause this issue

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Yay time to yank the bumper off and start going over everything. lol Any advice for diagnosing a WG failure? I have noticed it is still hitting its targets, but compared to my friends ZFR I do have to run a higher duty cycle to achieve the same boost. However, I am catted and still have the stock cat-back so I'm not sure how much of a contributing factor that could be to that given the turbos size.

cat causes back pressure so you will build boost faster as the gas cannot escape as fast as your friends catless.
wg failure do a simple vacuum leak down test and if you apply pressure to the port it should move.
same for bov but the boost test should open it.

Quote:

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Originally Posted by cobaltssoverbooster

cat causes back pressure so you will build boost faster as the gas cannot escape as fast as your friends catless.
wg failure do a simple vacuum leak down test and if you apply pressure to the port it should move.
same for bov but the boost test should open it.

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Well looks like the bumpers coming off and I have some testing to do. If the WG went bad it should be as easy as replacing the actuator correct?

usually
overheating can cause valve issues but its rare

On my ZFR it started doing the same thing....Boost was getting lower and DAL lower as well. I wired my wastegate shut in order to see if it was getting weak. Went out and slowly started adding throttle and boost climbed to 30 before I let off...So I then knew it was waste gate. I had so many problems with the can that ZZP has that I went to a Forge actuator.