Ok here is the problem, I have 2 manual boost controllers to control boost on the stock sequential system. I had the primary turbo set to about 14 psi, and the secondary to 13psi. It was fine for the past couple months. Now i am barely making 10psi on the primary and boost response is really slow. It is fine when the second turbo comes online, pulls like a freight train and holds steady at 13-14psi. But i cant figure this primary turbo issue out. I havent changed anything, it was sorta just a sudden change. Anyone have any ideas? What couldve caused this sudden change in boost response? Thanks in advance.

 

No one has any ideas? I have come to the conclusion that i have a major boost leak somewhere. I can hear a rushing sound from about 5 psi on. Now the only problem is locating the leak. I will keep ya updated on what i find, if anything.

 

Take a look at the Charge Control Valve (middle of the y-pipe). It's the one thing that separates primary boost from the secondary circuit, and if that valve isn't sealing well it could leak some pressure. Disconnect the vacuum hoses on the CCA, make sure it snaps back and forth quickly. I did once carefully disassembly my CCV and found that cleaning it up and greasing a few points restored that snappy response.

If it was a boost leak (and most boost leaks happen after the y-pipe), I would expect it to affect secondary performance more.

Dave

 

Problem located!!!!!!!! The coupler from the upper y-pipe to the intercooler had a huge tear in it, about 1.5 inches long. I never noticed it because if was right at the edge of the clamp. Got a new coupler and we are back to normal, actually better than normal. This thing has never pulled so hard before, i believe the tear was there since i bought the car but was not as severe. Boost is back on par and response in unbelievable. I guess im just seeing now the full potential of the car, without a boost leak.