Here is my problem. If I am doing a hard pull and shifting normally upon transition I am getting a weird fluctuation and I can hear the boost being diverted. I mean diverted as in away from the secondary turbo unabling the car to go into transition. But, if I am doing a hard pull and upon transition I "blip" the throttle the secondary does come online and the car pulls great. After doing a hard pull and "blipping" the throttle in order to cause the transition to occur, I then have a different exhaust note "more raspy/like n/a" and for a few moments I am unable to create boost. After I drive for a couple of minutes everything goes back to normal. To me, this sounds like something is sticking in the turbo control system, but to be honest I do not have the slightest clue what. I have inspected the vacuum lines (which are silicone) and they are fine, I have also checked the routing of them and the solenoids, all ok. And, tonight I performed the car on/car off test with the Charge Control Actuator, which is the one behind the coupler on the y-pipe. Any help would be appreciated.

Thanks, Jamie....

 

It sounds like a check valve problem - like the check valve to the vacuum tank is not functioning consistently. (During boost, the check valve has about 20"Hg on one side, and 10+psi on the other, which is like 20+psi total load. This is more stressful than during the KOKO test). Try swapping a spare into the check valve that's located in the bright green lines on the color chart, and make sure the arrow is pointing toward the manifold. Or just connect two check valves in a row.

If you managed to get a vacuum pump, connect it to that spot use it to pull 30"Hg vacuum on the vacuum tank and see if it holds consistently.

Dave

 

Which check valve are we talking about, im a little lost here... And the vacuum tamk that you are referring to is the one on top, in front of the uim?

 

The one on top is the pressure tank. The vac tank is the one under the alternator. The check valve is the one in the color diagram in the bright green hoses.

Dave