turbo lt1 boost leak
Thread Starter
Melting Slicks
Joined: Feb 2005
Posts: 3,467
Likes: 43
From: Auburn MA
turbo lt1 boost leak
I have a 94 corvette with a remote mount 76mm turbo and it seems like I am getting a boost leak. When I hear the turbo spool I can hear what sounds like air rushing out in front near the engine. I pressurized the system with a compressor and found air leaking out the air intake temp, sensor the throttle body plate, and intake coupler that goes on the throttle body.... I fixed them throttle body and intake elbow and i never got a chance to recheck the sensor before i tried taking it to the track. Needless to say tracking the car is suspended and i have no idea how to seal this sensor. What would work. And i am not 100% sure this is the problem either.
When I get on it I hear the turbo spool and i hear the air rush out and the car never comes off vacuum and it feels like it just falls on its face. Where else can I look? When I pressurize it with the compressor the air almost comes our as fast as it goes in.
When I get on it I hear the turbo spool and i hear the air rush out and the car never comes off vacuum and it feels like it just falls on its face. Where else can I look? When I pressurize it with the compressor the air almost comes our as fast as it goes in.
Thread Starter
Melting Slicks
Joined: Feb 2005
Posts: 3,467
Likes: 43
From: Auburn MA
Thread Starter
Melting Slicks
Joined: Feb 2005
Posts: 3,467
Likes: 43
From: Auburn MA
I have an idea Would an intake manifold gasket Leak cause this issue... because with the rate that the boost is leaking out this only seems to make sense
Last edited by Impala Balko; Jul 20, 2015 at 09:49 PM.
Burning Brakes
Joined: Mar 2005
Posts: 1,082
Likes: 115
From: Richmond Hill Ontario
This could be possible however, if the Intake manifold gasket was leaking this would usually cause High RPM at idle. What is your idle RPM?
Thread Starter
Melting Slicks
Joined: Feb 2005
Posts: 3,467
Likes: 43
From: Auburn MA
Burning Brakes
Joined: Mar 2005
Posts: 1,082
Likes: 115
From: Richmond Hill Ontario
Thread Starter
Melting Slicks
Joined: Feb 2005
Posts: 3,467
Likes: 43
From: Auburn MA
All the couplers check out fine now that I tightened the throttle body one down really good after my initial leak test
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Thread Starter
Melting Slicks
Joined: Feb 2005
Posts: 3,467
Likes: 43
From: Auburn MA
I totally uninstalled the blow off valve and i am still getting the same results. I hear the turbo spool up freely and i hear the rush of air escaping all while the car builds no boost and barely pulls 0 vacuum. It definitely sounds like the leak is in the engine bay... I think i may have to bring it to my tuner and have him smoke it out
Thread Starter
Melting Slicks
Joined: Feb 2005
Posts: 3,467
Likes: 43
From: Auburn MA
It looks like I am leaking bad out of my stock throttle body but not out the gasket but where the throttle body shaft comes out of the side of the body where the linkage... I ordered a new BBK throttle body hopefully this will cure it
Last edited by Impala Balko; Jul 27, 2015 at 10:43 AM.
Burning Brakes
Joined: Mar 2005
Posts: 1,082
Likes: 115
From: Richmond Hill Ontario
Waiting to see results
Thread Starter
Melting Slicks
Joined: Feb 2005
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From: Auburn MA
Team Owner
Joined: Mar 2001
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From: Boston, Dallas, Detroit, SoCal, back to Boston MA
Have you done the "soapy water" test?
Try pressurising the system w/o the engine running.
Just watch the pressure.
Faulty intercoolers fail in a spectacular fasion when they go.
They also make detectors that use smoke, so you can see the leak
http://www.smokewizard.com/
Try pressurising the system w/o the engine running.
Just watch the pressure.
Faulty intercoolers fail in a spectacular fasion when they go.
They also make detectors that use smoke, so you can see the leak
http://www.smokewizard.com/
Thread Starter
Melting Slicks
Joined: Feb 2005
Posts: 3,467
Likes: 43
From: Auburn MA
Team Owner
Joined: Mar 2001
Posts: 30,858
Likes: 293
From: Boston, Dallas, Detroit, SoCal, back to Boston MA
OK that's to protect the sensor and reduce signal fluctuation
You're good.
Have you checked the wastegate calibration?
Perhaps the BOV and the wastegate aren't happy working together.
You're good.
Have you checked the wastegate calibration?
Perhaps the BOV and the wastegate aren't happy working together.
Thread Starter
Melting Slicks
Joined: Feb 2005
Posts: 3,467
Likes: 43
From: Auburn MA
The wastegate has an 8lbs spring in it and i can adjust it up with a manual adjustable **** style boost controller, I did notice that had a tiny leak in it during my leak searches that has been taken care of but that still didn't cure it. The new TB should arrive tomorrow night hopefully and i should know more then. This has been such a frustrating ordeal the last couple weeks and I am half tempted to return it to NA. Once I get this sorted out I plan on getting a meth kit and i will have some questions for you about that.