i just finished some minor mods (downpipe, midpipe, racing beat catback, RE intake, Power fc and an exedy hd street clutch. My problem is that now my secondary turbo wont come online at all. The first turbo works perfectly, boosts to 12 psi than at the transition or should i say lack of transition (4200-4500 rpm) the boost drops down to around 7 psi and lowers still the higher the engine revs. I dont know where to start looking.

 

3 things to check



-prespool actuator

-y pipe actuator

-double throttle actuator



seems like your car is making boost, but the boost from the secondary is not getting to the manifold, as the primary turbo makes 10lbs your wastegate opens, and your motor uses whatever boost is left.... therefore boost starts dropping. meanwhile, either the secondary turbo is not being spooled, the butterfly on the y pipe is not openning (most likely), or the double throttle is not openning (probably not the prolem, cuz you'e actually losing boost) or a combination of these

 

did you take most of the intake pipes off to install the downpipe? including the y pipe? just make sure no nipples are unhosed or uncapped



also... did you cut the necessary wires for the power fc? is the power fc used or new?

 

i think i fixed it, i am slowly learning the pfc and the turbo setting was actually set for parallel not sequential from the beginning, so that took care of the boost now the only problems are the idle still jumps up and down from 1k to 2k and there is an oil leak on the right front of the engine, but performance is great, thanks for all of the advice/info.

 

your car will search for idle from anywhere from 30mins to a whole day... but your surging idle sounds like a vac leak

 

more than likely it is a vac leak, I am ordering a vac line kit pretty soon and diving into the rat's nest so hopefully it will solve the problems...