eniac

I use this setup in my shop often. It's the stock Turbo to IC pipe with adapters to plug an air line into the banjo bolt bung and the other end of the IC pipe plugged.

http://community.webshots.com/photo/...75908527XMMSYG

Alpine951

I borrowed this picture. This is exactly what i did. What I am wondering does air leak out of the turbo compressor outlet. See how there is a rag stuffed in the outlet. I am sure this is just to stop debris from getting in there and not make it air tight. Does air come out of the turbo at the out let when pressurizing the intake this way. I know the IC pipes go to the manifold but can some air makes its way through the hose on the manifold that goes to the isv which goes to the jboot which goes to the turbo? The reason I am wondering is I was not able to pressurize the system that well by going through this way. When I did it directly at the throttle body boot it worked better. The only other thing i can think of is the intercooler leaks because the connectors did not leak.

Mike Murcia

You should be able to pressurize the intake like that. There should not be a leak at your ISV. Even if there were, you would not only have air coming out of the turbo outlet, but also the air filter. One thing to keep in mind is that you'll have to add more air to build pressure that way than directly at the throttle body because you're having to fill both the intercooler and the intake manifold.

Alpine951

My ISV did leak so I removed it and plugged up the lines. I plugged up the end of the Jboot too. A motor mount fits in the end of the jboot nicely.

J Chen

The problem with using that little compressor
is that it's pumping all the time. With the noise,
it may be difficult for you to hear minor leaks.
I use a rubber hose as a stethoscope to listen
for leaks. It's much more effective.

Alpine951

If in fact the intake is building pressure then it should hold enough when I turn the compressor off to then check for leaks, unless there is a massive one right?

schnellfahrer

That picture is from my car. I didn't manage to get more than 5psi of pressure with the tirecompressor.
It was enough to hear a few leaks. When I turned the compressor off, I took about 10 secs for the air to escape. Plenty of time to check for leaks.
I had no air escaping out the turbo's outlet nor inlet.

Alpine951

Thanks Eivind. Well I think the next step is to get to radio Shack and make a Blink code tester.

Mike Murcia

5 psi is not a lot. I found that some leaks needed about 18 psi to show themselves.

schnellfahrer

I know Mike. You should use a more powerful compressor.

ibkevin

Wow, great thread! I searched last week during my turbo swap and ensuing vacuum leaks for a through test aparatus setup with marginal success.

I tested mine with the Porsche approved fuel filter housing rig (funny, I had a Purolator w/a 928 part #, and made in W Germany) at the Jboot but forgot about the ball-gag for the exhaust. My Jboot is new so I didn't sweat it too much. When I pressed the sys up there was a huge leak but the dull sound make it hard to find, it was to the rear of the intake manifold. That really ties it down! I do like the post turbo test setup much better with the PVC cap.
Hos, great link you've got there. I just learnt alot of that the old fashioned way.
BTW, I thought my stock boost gage was dead but instead she reads ambient press(barometer), where does this tie into the intake manifold? The manifold was the last intake system part removed before my barometer problem.