Ok, in my last thread I mentioned that ever since my upgrade install (GT28 hybrids, injectors, EVO I/C's, larger Y-pipe, TB and plenum, exhaust/headers, GIAC flash) my car just didn't seem right. I would make gradually make boost; at 3k RPM I would make .6 bar, 5k .9 bar, and redline 1.1 bar. A datalog showed there was no boost deviation by the ECU. The shop smoked the motor and there were no intake leaks. So I suspected either the DV's were leaking or something was up with the WG actuators or boost control system. I pulled off the Maxspeed DV's and threw my stock ones back on and it didn't help. To try and single out the problem, I removed the hose from my boost control solenoid going to the WG's and capped the solenoid. Took it for a spin and voila! my boost is back! And boy is it ever back. Part throttle makes 1 bar well under 3k RPM. Knowing I have no WG's and therefore really no boost control, I had to be careful with the throttle. So now I suspect the boost control solenoid is leaking causing the WG's to start opening early. I'm going to order a new solenoid Monday and see if that helps (unless any vendors on here have them in stock and can ship them out tomorrow, wink wink). The only other question I had was if they maybe reversed the two hoses on the output end of the solenoid, or do they both receive the same pressure? The other one goes over towards the DV's.

The last question I have is what does the solenoid do (identical part to the boost control solenoid) right before the DV's? I assume vacuum passes through it, but there is a check valve right before it that keeps boost from entering this system (understandable as right after this solenoid a hose goes over to the vacuum canister).

I can't wait to get my boost in check, so I can make strong boost but not overboost....6 months now I've been trying to get this car sorted out.

 

No one?

 

I don't have an answer to your question - wish I did, but I would question the shop that performed the upgrade for you.

Did they not test run your car and look for these issues? Who is it that performed the upgrade?

Good luck with your final resolution.

Rich

 

Did you upgrade the wastegate actuators? What is the crack pressure set to? Total speculation here, but a weak spring or low crack pressure could lead to the actuators "seeking" while the N75 is trying to cycle them to the desired boost.

 

1 bar springs. They said the actuators are set right. Now, if they were set too soft, wouldn't I have the same boost problems even with the boost control solenoid disconnected?