umm leak or something

[dmince]

I just got my car back from gettign the head redone and now i am leaking boost. im not sure where or if its just my actuautor being dumb. so i disconnected the line to the actuator and it boosted strong till it hit fuelcut, now im not sure if thats telling me if my actuautor is bad or if ive got a leak in a line somehwere. if anyone has a better idea let me know. id greatly apreciate it. i searched some but didnt find the same scenario really. thanks

 

[GST with PSI]

By disconnecting the actuator vacuum line you only created a larger vacuum/boost leak. The purpose of the vacuum line going to the actuator is so the actuator can see manifold pressure. By disconnecting the line, your waste gate is staying closed permanently. When you went for a spin with the vacuum line disconnected, boost was probably leaking more than it ever had originally. Not only that, but nothing is going to stop your turbocharger from spooling accept in your case as you described, fuel cut.
A bad actuator won't have anything to do with a boost leak unless the diaphragm itself leaking. Use can use a hand held vacuum pump to test the actuator. If the diaphragm doesn't hold a vacuum it is bad. Or, if you can disconnect the actuator arm from the waste gate do this: Push the actuator arm all the way toward the diaphragm body. With the diaphragm and arm depressed, put your thumb over the nipple located on the diaphragm body. If the actuator arm stays at the position you originally pushed it in to, and doesn't move until you remove your thumb, the actuator is good.
If it's a boost leak your after, use a boost leak tester connected at the rubber intercooler hose at the j-pipe. Pressurize the system to about 13 psi or so. Fix the larger leaks you can audibly find first. For the smaller leaks you can't hear, use a spray bottle filled with soapy water. Spray everywhere until your system holds steady for a good 15 seconds or so. Make sure you pinch off the line going to the PVC valve.
Good luck...

 

[grnchevyz]

Just a note, how did you come to the conclusion that you're leaking boost? The feel? The sound? just asking because if you know you're leaking boost, the first thing is a boost leak test and not removing vaccuum to the wastegate.

GST with PSI hit it bang on, do a boost leak test and take it from there.

One more question, how does the car feel or not feel? Maybe its something in the head rebuild that was unplugged and forgotten? I know when I replaced my vaccuum lines I had an extra one and couldn't figure out what it was so I plugged it. turns out it was the line going to the factory boost controller. The car didn't feel right and tought boost leak for sure. plugged it back in and I was happy again