My car was running perfect until a couple days ago my Hi boost was peaking out at like 8psi normally it's 19psi. My lo boost is 14.5 and only goes to 7.25psi and no boost controller I'm supposed to be at around 10psi but only goes up to 5 or 6 psi. Is that a vacuum line issue or do you think my GReddy Profec B boost controller is broken? Any suggestions/help would be greatly appreciated.

 

Trying to understand your statement... if wastegate boost is 10psi and you are only seeing 5 or 6, it is a mechanical failure meaning the boost controller has nothing to do with it. You should be checking for a leak - such as cracked exhaust manifold.

 

So wouldn't be something minor like a vac hose?

 

If you remove a vacuum hose from the wastegate, boost will increase. If the boost controller failed, you would see wastegate boost. You can not set boost lower than wastegate with any boost controller.

Depending on how you have your wastegates plumbed, it could be possible that you have a boost leak on the intercooler pipe side of things.

 

x2..or a crack somewhere else on the hotside(pre turbo)

 

I have the GReddy TT kit and just recently had a new bumper put on so I'm hoping it's the IC piping is loose and no cracks anywhere. Thanks for your guys input and will post what I have found out.

 

Checked everything a friend suggested vac line and another shop suggested silicone boots on intake side. It ended up being a split vac line that goes to my BOV. Back in action, and thanks for the input/help. Glad it wasn't a cracked manifold or something serious.