About out of options...

[Jiggalude]

I've hunted down and repaired every single boost leak that I could find but I'm still leaking boost when I test. I get to about 20 PSI or so, and will leak to about 10 in less than 30 seconds. The remaining 10 psi or so will take a little while longer to leak out. I've replaced the TB O rings, TB gasket, the intake to TB gasket, I had a hole in the valve cover I fixed, IC hose I fixed. Fuel injector O rings were leaking and i fixed them. I replaced all my vac. lines and also eliminated some as well. The only things I have yet to replace would be the intake manifold gasket and the boost source line for my boost gauge. Any body have any other suggestions as to what would be leaking? Would a leaking intake manifold gasket leak down that quick, but not make any noticeable noise?

 

[2gGSXEclipse]

Sometimes it leaks out of the Intake Manilfold gasket and you cant hear it. You can spray some soapy water on everything and see if you get any bubbles from it. Good luck with your fidings

 

[And_44]

Yea, if it's a large gap in your IM gap you probally wouldn't hear anything.

 

[LiquidX]

Very possible that your IM gasket is bad but you need to spray. Another thing to help, is if you haven't already, replace ALL of your vacuum lines and put zip ties on the connecting ends. Spray EVERYTHING that see's any vacuum or positive pressure.

 

[92AWDTalonTSI]

+1 on the zip ties.

You could also have a leak in that gauge line. When I got my car I had a slice in the boost gauge line where it went through the firewall. The zip tie on the gauge was also before the barb and the line would pop off the gauge under boost.

 

[9!'clipseDOHC]

To make sure its not leaking past your valves and out through your exhaust, get your #1 cylinder to TDC and then rotate the crank clockwise 6 teeth and see if that helps. Could easily be the IM gasket though, I'm pretty sure I have a small leak on the underside of mine.

 

[GSXSixteenG]

Don't rule out a cracked intercooler...

 

[LiquidX]

Don't rule out a cracked intercooler...

This is why you should be boost leak testing in 3 separate sections. At the TB elbow (fix all leaks), then move to pre IC (fix any leaks), then finally full system pressurization at the compressor inlet.

If you aren't already, be sure to use soapy water in a spray bottle. You cannot rely on sound or the very unsafe method of carb cleaner/starter fluid.

 

[9!'clipseDOHC]

This is why you should be boost leak testing in 3 separate sections. At the TB elbow (fix all leaks), then move to pre IC (fix any leaks), then finally full system pressurization at the compressor inlet.

If you aren't already, be sure to use soapy water in a spray bottle. You cannot rely on sound or the very unsafe method of carb cleaner/starter fluid.

Exactly right!