I was hoping to get some insight on my boost leak which I have battled for a long time. I read the trouble shooting page, and it doesn't help me much.

My boost pattern is 10-8-7, and there is an audible high pitched leak sound when the secondary kicks in (obviously a boost leak)

I have;
Checked the air bypass valve and CRV and replaced them.
Replaced all of the couplers.
Tightened the stock air box lines and to the Y pipe with hose clamps
Checked all the hoses that are visible to the eye without taking the intake manifold off

Thanks for any insight, because I don't really want to take everything apart without some idea as to where it could be coming from.

Kevin

 

Did you check all the lines leading to the CCA? If boost pressure is not applied to both sides of the CCA, it will not open the CCV completely, stifling boost from the secondary turbo.

 

What is CCA the acronym for?

 

Charge Control Actuator

 

You can't acheive 10psi of boost on the primary turbo and then have a boost leak on the secondary turbo. Its impossible.

R.K.

 

It's not impossible. You can have a leak at the CRV connection. This would not effect the boost before the transition as the primary and secondary are isolated from each other by the charge control. It would effect the boost after transition as the CRV is supposed to be closed and the primary turbo is now joined with the secondary.

I'm not suggesting that this is the problem here, but I'm just stating that its not impossible to have a leak which only effects the second half of the boost pattern.

 

Thats true. Its very rare that it leaks from there. Either way good luck to the original poster.

R.K.

 

From the Auto Sport Racetech site: "Chamber B is always connected to the Primary Turbo Compressor and normally will have 0 to 12 psi of boost pressure applied. Chamber A is connected to the Charge Control Solenoid, from 0 to 4,500 RPM a vacuum from the Vacuum Chamber is applied, above 4.500 RPM the Secondary Turbo Compressor is applied to chamber A.
From above 4,500 RPM with Secondary Turbo Compressor applied to Chamber A, when the Secondary Turbo is producing the same or more Boost than the Primary Turbo, the Charge Control Actuator's spring will allow the Charge Control Valve to open, allowing the both the Primary and Secondary Turbo provide boost."

The line to chamber B can be intact, with no loss of primary boost, but if the line to chamber A is leaking, you not only have a secondary boost leak, but the CCV won't open.