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Had trouble with boost, only getting 11 or 12 psi. Checked the vacuum lines and they were on wrong so I fixed that and now there is no upper limit to boost. So I tore everything apart this weekend and I think the wastegate may be bad.Checked the resistance of the stock wastegate actuator and it is within specs. Hooked 12 volts to it and it will cycle on and off with no problems. Tried the Power EBC and I had no high limit for boost . Checked the solenoid for it and it is working correctly. One question, does the vacuum hold the wastegate shut or does it open it when applied. The reason I ask is that the stock solenoid is closed when off and the aftermarket one is open when off. I currently have the wastegate hooked to the out of the stock solenoid and the intake nipple hooked to the in of the solenoid with the hose coming from the turbo capped off. With this setup I do not have any upper limit to boost it will willingly go past 1.5 atmos. Is there any way to check the wastegate short of taking it off the car ? Thanks for your help. Keith
 

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keithsevo said:
Had trouble with boost, only getting 11 or 12 psi. Checked the vacuum lines and they were on wrong so I fixed that and now there is no upper limit to boost. So I tore everything apart this weekend and I think the wastegate may be bad.Checked the resistance of the stock wastegate actuator and it is within specs. Hooked 12 volts to it and it will cycle on and off with no problems. Tried the Power EBC and I had no high limit for boost . Checked the solenoid for it and it is working correctly. One question, does the vacuum hold the wastegate shut or does it open it when applied. The reason I ask is that the stock solenoid is closed when off and the aftermarket one is open when off. I currently have the wastegate hooked to the out of the stock solenoid and the intake nipple hooked to the in of the solenoid with the hose coming from the turbo capped off. With this setup I do not have any upper limit to boost it will willingly go past 1.5 atmos. Is there any way to check the wastegate short of taking it off the car ? Thanks for your help. Keith
If the wastegate was giving you 12 psi before then it is fine. With a direct hook up of a vaccuum/boost hose from the boost source to the wastegate actuator you will get 12 psi of boost. The stock boost solenoid should be configured as a bleader valve. There should be a line going from the boost source to the wastegate actuator with the boost solenoid comming off of a T connection in the middle. The stock solenoid is closed allowing no blead off and giving you 12 psi unless it is cycled open by the ECU allowing boost to bleed off before reaching the wastegate actuator. Real bad diagram to follow:

{Boost source}______________________________________{....Wastegate actuator}
. . . . . . . . . . . . . . . . . . . . . . . . . T . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . | . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . | . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . .{soleniod}. . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . | . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . | . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . .{intake pipe}. . . . . . . . . . . . . . . . . . . . . . . . .

That would be the boost source going to a T, then from the other side of the T to the wastegate actuator. On the bottom part of the T you have another rubber hose leading to the stock boost solenoid and from there through another rubber hose to a nipple on the intake in the area of the air filter box.

If that is how you have it hooked up, without the ECU connected you should get 12 psi and with the ECU connector on the solenoid you should get 19 psi tappering down to 16.5 or 17 psi.

Keith
 

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keithsevo said:
I tried hooking it up like the diagram and could only get 12 psi. Keith
Have you checked the ECU connection to the boost soleniod? Hooked up like I showed you is the correct method, and if the ECU is controling the solenoid it would give you correct boost pressure....

Get the ECU pin out diagram from road race engineering, and do a continuity check on the boost control solenoid wires from the ECU connector all the way to the solenoid connector. There has to be a problem somewhere in the wireing.

Keith
 
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