They say necessity is the mother of all invention. Awhile back I had to figure out a way to pressure test my car to check for a boost leak. I found all of the parts at Lowe's. I got two 4" rubber end caps and used those to cap off my exhaust. Then I bought a 2" (inside diameter) pvc end cap and drilled a hole and put a tire valve stem in it. Once everything was installed I was able to pressurize my car with an air compressor. The tire valve also allowed me to stop adding air yet maintain pressure. This is also a great way to test your exhaust for leaks too.

 

Good job !

I had done the same thing a couple years ago with a capped off metal pipe . Adding the tire valve is new .Takes a while to preasurize but you find all boost and exhaust leaks .

 

results?

 

Thanks Booger! It actually pressurizes to 10 psi in about 20 seconds, a lot faster then I thought it would too. Of course it all depends on how high you have your air compressor set to.

 

I found my leaks. It works!

 

How can you visually see air leaks, or did you just listen? I've heard of adding smoke some how...

 

I had the air comp. set to 40 psi....listened for the leaks and just shut the air off when I found them all .

 

Trust me you will hear them. The noise should get you close enough. You can always then resort to a spray bottle filled with soapy water.

 

Bumping this thread up.

I have a greddy TT setup. Im getting some pretty bad leaks. Supposed to be building 15 psi but can only reach 5.5. So what I am going to do is take off both air filters. Plug one side with a pvc pipe and the other intake with a PVC pipe with filler valve. Does the exhaust need to be blocked off? Because I have flex pipe welded in there and they both kinda have a small rip in it so there is no way that it will hold any air in the exhaust.

If I leave the exhaust uncapped will I still be able to find leaks? Or should I just un bolt it from the downpipes and plug it up from there?

 

it must be a sealed system. so you will have to plug your downpipes

 

nice diy!

 

figured id just bring this back instead of make a new thread..

i did a boost leak test today similar to this, i just blocked it off at the throttle body though and didnt test the motor or exhaust...

anyway while doing this i found a leak at my maf..where the actual maf sensor screws into the plastic tube there is a small leak that i couldnt do anything for, i even added a thicker rubber o-ring which helped but i still hear a very faint leak, my only thought is to build an actual pipe to get rid of that stupid plastic tube that the maf sensor goes into like i saw member big c had for sale on here a while ago, any suggestions besides that?..

also my main concern, now i am doing this with the car off which i assume everyone else would too, so while doing this my bypass valve has a small leak inside where the blue diaghram closes..Should it be completely sealed when the car is off and i am doing this test or is this normal? It seems to me like it should be closed but im not sure as the car is off with no vacuum or anything, as soon as the pressure builds it starts a small leak i could hear and feel out of the end while doing this test