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guyd_15
03-05-2006, 08:01 AM
I changed the head gasket, since then the boost is uncontrollable. The boost gauge gets pegged almost immediately!!! My boost is controlled by a vacuum line from the intake to a grainger then to the swingvalve. What do you think, a stuck wastegate, bad g valve or leaking line between g valve and swing valve? HELP!
Guy

Wink
03-05-2006, 08:58 AM
you hit the nail on the head. Check the wastegate by disconnecting the arm from the swingvalve and see if it is binding or not. Check all hour vacuum hoses to make sure that you don't have any cuts/tears in them creating the leak. Not to mention making sure you have them connected properly. Try removing the G-valve to see if that's the culprit. If no changes when removed, then we know that's not it.

Good luck and report back when you know something or find something,

Wink

Dave
03-05-2006, 10:58 AM
you hit the nail on the head. Check the wastegate by disconnecting the arm from the swingvalve and see if it is binding or not. Check all hour vacuum hoses to make sure that you don't have any cuts/tears in them creating the leak. Not to mention making sure you have them connected properly. Try removing the G-valve to see if that's the culprit. If no changes when removed, then we know that's not it.

Good luck and report back when you know something or find something,

Wink

With that said take a precaution in removing the g-valve altogether, because the boost with a Garrett WILL hit over 20psi instantly then cut out at 14.7psi. So when removing the g-valve and testing it all out just gradually get into the gas. That will of course tell of you if you have a bad can or not. Which I dont think it is, sounds a lot like vaccum related.

What kind of turbo and exhaust are you running?? Are you sure you didnt change ANYthing else?

Wink
03-05-2006, 12:57 PM
Say what?!?!?!!


What I guess I meant to say was remove the G-valve and run the wastegate directly off of the vac/boost source. This way it should only see 7-8 psi. If it spikes to overboost still, then we know the wastegate actuator assembly has a burst diaphram.

Force Fed Mopar
03-05-2006, 06:22 PM
How much does your gauge read to? Sounds kinda like a stuck or bad G-valve. You didn't happen to fix an exhaust leak when you did the head gasket did you? If you had a leak and had the G-valve set with it leaking, fixing the leak would be making it boost higher. Exhaust leaks= less boost.

cordes
03-13-2006, 08:06 PM
You could have the ball in the G valve backwards. It should be on the side that the manifold vac line connects to.