Contributed by Virus77
This is something that is pretty handy and costs a few bucks, eveyone should make one.
Yours will look different but will do the same thing.
Parts you need:
-The coupler you use to connect your intake pipe/mafs to your compressor intake.
-a pvc end cap from home depot that fits snugly into your coupler. (so its the same size as your compressor inlet on your turbo)
-simple hose clamps to hold things together.
-some form of air compressor (personal, shop compressor, foot pump, etc…) Further testing showed you need a pretty decent pump to make this effective, shop pump or home air compressor would be best
-a fitting to attach your air compressor of choice to pvc endcap (refer to pictures)
Here are the pics:
The end cap needs to have a hold drilled in it so your fitting can attach to it. This is where you will presurize the system from.
you insert the end cap into your silicon/rubber coupler and clamp it down (I had that extra silicone bend for my new maf piping I was gonna make so im using that for the time being)
The other side of the contraption gets attached to your turbos compressor intake (where the air filter/mafs coupler would normally go).
if you have a bottom mount setup and its difficult to get to the turbos intake you can also pressurize the system from after the mafs and use your cars intake piping as an extension to the turbos intake. However when doing this make sure the any line going to the intake are plugged. For instance if you have a valve cover breather line/ PCV / catch tank going to the intake pipe it needs to be plugged or else you are going to pressurize your valvecover, crankcase, etc and it wont work. Although I did find a valve cover gasket leak like this
Then you attach your choice of air compressor to the fitting on the end cap side and you pressurize the system. Check your boost guage and presurize the system up to like 15 psi or whatever youwould run to see if anything pops off.
Thats pretty much it. Obviously the motor is off while you do this so If you have the slightest leak it will make a loud noise and you will find it, also if your intercooler connections are leaking it will leak and you will find those aswell. Depending on the size of your leaks you might not be even to pressurize over a few psi, so just keep fixing leaks till you hear no noise.