The waste gate solenoid is controled via the ECM and they modulate the ground side of it.

The control is called "Pulse width modulation"


Before we rip the wiring al apart. I am not convinced that the issue is the electrical side of the thing.

Have you had any codes pop up (SES light coming on) ??

Whats the vacuum reading at the vacuum pump (direct connection to the pump[ with a gauge ) ???

This should be 26"hg and steady, if the needle on the gauge wobbles all over, the pump is shot.

With the system hooked up, you should have good vacuum to the solenoid and to the waste gate actuator on the turbo.

With the engine running the waste gate arm on the turbo should be stable and you should not be able to move the actuator rod back and forth.

There should be at least 20" hg vaccum at the waste gate actuator.

If not there is a leak somewhere.

When the solenoid is activated the vaccum is bled off to allow the wastegate to open and reduce or maintain the boost level

Wastegate solenoid failures are common on these. If the solenoid fails electrically it can set a code, if the failure is mechanical and the thing leaks off the vacuum when it should not, there may be nothing more than NO BOOST.

Check the vacuum readings first and be sure you have vacuum all the way from the pump to the waste gate actuator. If not trace it back one point at a time to find out where its failing.


Keep us posted.

Robyn