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Overboosting 14b

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naw9119

10+ Year Contributor
54
0
Mar 24, 2010
Athens, Alabama
Help guys. My car is boosting up to 25+ running a stock turbo and the actuator connected to the Turbo elbo. I've checked all my lines and no leaks. I searched the forums and it all leads to not having enough backpressure in the exhaust. But I didn't think a 14b could hold boost that high. It won't drop off the crazy boost untill I back off the throttle. Can someone please help me with this issue it's driving me insane.
 
How big is your down pipe? o2 housing or tubular o2? tube manifold or stock manifold?
 
That's what I thought. I've got a gizzmo ibc boost controller. But it still does the same thing even though the wastage actuator is hooked straight to the turbo outlet elbow.
 
Take the clip off thats holding the wastegate actuator arm to the actual lever that moves the flapper and make sure you can move the lever freely by hand and its not binding or anything.

Sounds like a wastegate issue to me.

Ive got crazy boost creep like that with everything functioning properly but thats because I have a tube manifold, unported 16g, tubular o2, and 3 inch exhaust.
 
actuator itself wont(or doesnt really want to) move, but if you take the clip (c clip) off the "rod" coming out of the actuator and just move the arm thats welded to the shaft going into the turbo that the wastegate flapper is actually attached to you should be able to move it.
 
Scratch the overboosting problem on my way to work today
My car started smoking like Cheech and Chong, no boost did my turbo just crap out on me or maybe worse?
 
that could be several things check the turbo impeller see if it still spins and check how much play is in the shaft and also check all of your intercooler piping to see if you didnt blow off a coupler and double check your wastegate
 
it possable you could have killed ether of them if you dont have the car tuned for 25 psi
 
Will you blow white smoke if blow off a intercooler pipe? It was a lot of smoke so much I couldn't see the car behind me.
 
+1 on the head gasket. 25 pounds boost on a stock, older motor, is a recipe for disaster. Sounds like blown head gasket. Stop driving and do a compression test. Then go from there based on your resualts.
 
I would do a cylinder leak down test after the compression test if you find low compression on one or more cylinders that will let you know where the leak in the cylinder is. I'm gonna vote head gasket at this point as well.
 
Geeze. You know that you are overboosting yet you keep doing it anyway? What did you think would happen? Now in addition to just checking the wastegate flapper you will also need to check for shaft play and a blown headgasket (compression and leak down). Lesson learned? I hope so.

Hopefully it's just the turbo and not the motor. Only doing those checks will tell you. Either way, befor you get this car back on the road you will need to verify that the wastegate is operating and if it is port the hotside and o2 sensor housing. While the 14b's are amazing little turbos they don't last forever (especially at that boost level). Case in point mine let go last night too.
 
Scratch the overboosting problem on my way to work today
My car started smoking like Cheech and Chong, no boost did my turbo just crap out on me or maybe worse?

time for a new turbo! im in the process of fixing the same issue. not the same turbo as you'rs but running that 14b at such a high boost took its toll. sounds like the compresser wheel jurnals are shot, creating excessive shaft play, and sucking oil through the intake and ic piping causing the "Cheech and Chong" effect LOL. i had people yelling at me while i was driving down the road. "go fix your car!", that kinda thing..... but take the lower ic pipe of and check for oil in the pipe. if its there, then the shaft play is bad. go big 16g and you should be good bolts right up:thumb:
 
Well the motor is far from stock and not that old. As far as driving with boost problems, I baby the car everywhere I go. I'm thinking it's the turbo but I'll do some investigating Monday and keep you guys up dated. I have a new head gasket, 16g and another 14b in the garage so it's really not that bad I've been expecting the turbo to some time after the engine was rebuilt but we will see thanks for the help so far!
 
Before you replace the turbo swap out just the wastegates. As for the white smoke you could have blown out the seals in your current turbo.
 
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