doesnt boost at all now and no vaccum

[boostedgst90]

i bought a 1st gen gst and i drove it for 19 miles and it doesnt boost at all now and no vaccum........### should i look for....should i compress the turbo with a fiting and i air compressor and some soapy water...or could it possibly be the waste gate or turbo bad the car has 143,000 miles

 

[92dsmtalon]

Id test it with the compressor 1st, find and seal any and all leaks, if it still does it, then look into other options, sounds like a boost leak to me though.

 

[boostedgst90]

ok today i took apart all my vacum lines and charge pipes.... nothin is bad on that...but i did find that when i took my head sheld off my car it has 3 crakes on the exhuast manifold could that be the reason i can only get maybe 2 to 3 psi at like 5,000 rpms....and how much would a knew one run me price wise

 

[turbosax2]

You MUST do a proper boost leak test. Visually inspecting everything will not show boost leaks. Read the forums for how to perform a boost leak test.

 

[MrBoxx]

1. Spell check, grammar check, punctuation check. Seriously.

2. Boost leak check. A real boost leak test with a tester, an air compressor and a friend to watch the aftermarket boost gauge.

3. Check for shaft play on the turbo. Check to make sure the wastegate armature hasn't fallen off the wastegate flapper arm. Check to make sure your boost gauge hose hasn't fallen off your tee and that there aren't any leaks or holes in it.

 

[oldman]

1. Spell check, grammar check, punctuation check. Seriously.

And CAPITALIZATION!!! Double seriously.

 

[boostedgst90]

I checked for shaft play there is none. I checked the wastegate arm. Yet again thats fine. but i did do a boost leak test yesterday i was asking if the manifold is bad if that could cause the turbo not to spool correctly. The manifold has 3 long cracks on it and you can feel air blowing out. sorry guys im a newbie. Thanks

 

[1slo1g]

If the manifold is cracked that would def be a problem. Get a new manifold and the before you drive it do the boost leak test.

 

[oldman]

If you had air rushing out of the exhaust manifold during a boost leak test, you've got bigger fish to fry because exhaust manifold is not a part of a boost leak test. To answer your question, YES pre-turbo exhaust leaks will affect your spool and boost level but I doubt it will result in 0 boost.

 

[boostedgst90]

it has boost but only like 2 to 3 psi. i got a manifold that my mechanic is putting on. but before that im gonna run to the hardware store to make a boost leak tester. what kind of sealer should i use for the valve stem?. i was thinking some silicone. but throw some things at me..thanks

 

[zippyshoe]

In addition to replacing that exhaust manifold, I would also recommend a proper boost leak test for two reasons:

1. To detect presence of any leaks in the intake path. (obviously)
2. To verify that your boost gauge is functioning properly.

A cracked exhaust manifold could provide an alternate path for exhaust gases to escape rather than passing through the turbine blades of your turbo.

 

[boostedgst90]

Ok.. I'll post up the results later on tonight or tommrow. depends on when i can go work on my car...but thanks again guys. And if you guys want to give me some more suggestions. Im open to them

 

[oldman]

it has boost but only like 2 to 3 psi. i got a manifold that my mechanic is putting on. but before that im gonna run to the hardware store to make a boost leak tester. what kind of sealer should i use for the valve stem?. i was thinking some silicone. but throw some things at me..thanks

CAPS!!

Get one of those rubber plug type valve stem, drill a smaller hole on the cap and pull the stem through the smaller hole and it should seal just fine, you can apply some RTV around the edeges for extra protection.

 

[Smitherines]

CAPS!!

Get one of those rubber plug type valve stem, drill a smaller hole on the cap and pull the stem through the smaller hole and it should seal just fine, you can apply some RTV around the edeges for extra protection.

SPELLING!!