Recently I have read a few threads in regards to people finding boost leaks (velociabstract and grip grip). Just wondering how they found the leak and what the symptoms are that forced them to search for the leak.

I know when I had turbo cars you could just compress air into the turbo inlet and listen for a leak throughout the setup.

 

You can test the same way. PVC 90 and cap, thread an air compressor fitting into the cap. attach with a short piece of silicone connector and two hose clamps to the TB. Slowly turn up the regulator on your air compressor and listen. You have to cap off the PCV system hoses that attach to the bottom of the TB, and put a short loop of hose across the two vacuum fitting on the top of the SC. I could pump up to 15 psi until the tester popped off the TB. I had no leaks. After you are done be sure to pump the brakes a few before moving the car.

 

In my case I took the upper manifolds off to instal the Needswings catch can and didn't use any locking sealant on the bolts when I put them back on. During the next track day the car was running fine at WOT but a little strange at idle. On the way home I got a code. Poking around I discovered the bolts had backed almost all the way out. Another time I broke one of the bolts. Anyway, I've had them off 4 times in all and if you don't do everything right something will leak. If you've never had them off don't worry. The symptoms are an idle that just isn't perfect. A bog or hesitation on gentle throttle openings. A "cough" if you lift from WOT suddenly at high rpm. At least that's what I've observed. One of my leaks was from forgetting to instal the cork O rings under the outside bolts. One of those oversights that can occur. All I can say is if you have them off for any reason, use something like locktite blue and follow the instructions. (I didn't once and guess what happened even with the blue)

Les

 

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Re: Boost Leak??? - 04-28-2011 , 12:32 PM



You can test the same way. PVC 90 and cap, thread an air compressor fitting into the cap. attach with a short piece of silicone connector and two hose clamps to the TB. Slowly turn up the regulator on your air compressor and listen. You have to cap off the PCV system hoses that attach to the bottom of the TB, and put a short loop of hose across the two vacuum fitting on the top of the SC. I could pump up to 15 psi until the tester popped off the TB. I had no leaks. After you are done be sure to pump the brakes a few before moving the car.

 

A couple summers ago I took off WOT from a stop and something popped, then the car started missing and backfiring. It turned out I popped out a sensor in the plenum (that's how my shop described it). I thought I blew the s/c so I was very happy at the easy fix. I suspect the dealer did not tighten it when they replaced my s/c intercooler earlier that year.