kick7ca

I hooked a regular bycicle pump up to the hose which leads to the wastegage diaphram, and my wastegate opens with the slightest application of air pressure.
Meaning when I come down reasonalbly slow on the bycycle pump the wastegate opens right up. I might expect it remain closed longer. Does it need alot of pressure to open or a little?

....I am suspecting that the wastegate is opening too early and preventing full boost.

gergrx7

wastegate opens at 5.5psi

kick7ca

thanks, but in the FSM it instructs you to note if the rod moves at 10psi. (?)

I need to figure out a way to measure this, couldn't find a pressure testor at store..

gergrx7

how could the rod move at 10 psi when your car only runs either 5.5psi(s4) or 7.5psi(s5)
do you haev boost gauge? if so use bike pump till you see 5 psi then see if it moves

NZConvertible

The wastegate actuator should start to move at ~4psi. All wastegates start to open before max boost is reached, which slows the rate if boost increase. This is called wastegate creep (totally different to boost creep).

The FSM says to apply 10psi pressure. It does not say at what pressure the wategate actually opens. It simply instructs you to check that the actuator rod moves as pressure is applied and removed.

Note that if you connect a bike pump to the actuator, you have a closed system, so it will only take a small movement to get 4psi pressure.

kick7ca

Yeah 10psi is applied to check the diaphram, which I did, and everything appears to be functioning correctly. My problem (intermittent power loss and whistling) must be vacuum leak(s).

Thanks

SureShot

Classic symtoms of a crack in the TID.
Under load the torque of the engine will pull & pinch a crack at different times, which can dirve you nuts trying to find the problem.