help with boost leak test

[bstevenson]

I made a boost leak tester today and hooked it to the turbo and went to pressurize the system, I blocked off all of the hoses that go to the accordian hose but needed to see if there are any other hoses that I need to block off or unhook in order to perform a test correctly.

I hear air coming from the backside of the intake from below the fuel rail I believe.

 

[bstevenson]

btw if I block off one of the vacuum hoses circled in orange, the leak stops
if that helps out

 

[bstevenson]

bump. . .help!!!

 

[jdub]

That is your EGR valve modulator...the vac source is on top of the throttle body and is routed down the hardline to the VSV shown in the pic on the back lower part of the intake manifold. The VSV should be closed at idle or with no power on the car....no vacuum should be present at the modulator.

BTW - from your discription, this is not a boost leak...it's a vacuum leak.

 

[bstevenson]

That is your EGR valve modulator...the vac source is on top of the throttle body and is routed down the hardline to the VSV shown in the pic on the back lower part of the intake manifold. The VSV should be closed at idle or with no power on the car....no vacuum should be present at the modulator.

BTW - from your discription, this is not a boost leak...it's a vacuum leak.

If I pressurize the system (like I am doing) w/the car off should the vsv be closed. . .not allowing air to pass through to the egr system? I realize I have a vacuum leak that I will need to fix, but should the vsv be open and allowing air to pass through or not?

 

[jdub]

If I pressurize the system (like I am doing) w/the car off should the vsv be closed. . .not allowing air to pass through to the egr system? I realize I have a vacuum leak that I will need to fix, but should the vsv be open and allowing air to pass through or not?

The VSV should be closed at idle or with no power on the car....no vacuum should be present at the modulator.

I think that's what I said

 

[Supraboy89]

I usually check mine by putting a tennis ball on the inlet side of the turbo to block it off and disconnect the rubber hose from the 3000 pipe. loosen the other clamp on the same rubber hose to turn it so I can blow into it.If no air passes through you have a good seal. most of the time your leaks are in the plumbing from the turbo to the TB. You will notice a vac leak in the intake because it will make it run bad or you will hear a hissing sound around the intake.

 

[bstevenson]

So I did another pressure test and it seems as though air is leaking out around two injectors like crazy. . .I would imagine that I can just replace the o-rings and hopefully i'll have no more air leaking