exhaust or boost leak?

So i recently bought a vr4 galant after selling my nissan 240sx I like the car a lot, but after driving it for a couple days and then noticed that i could hear an odd sound like i had a hole in my exhaust system. I looked under the car and other a small dent in my downpipe there was nothing. I went for a drive to try and figure it out and when i reached boost i noticed I was only at 9 lbs when I'm supposed to be running at 15? could it be that something came loose and thats why the car sounds and runs like crap?

any help would be great

 

[solidviper89]

exhaust leaks after turbo (i.e. downpipe) don't directly affect the performance. If you have an exhaust leak where exhaust manifold meets the head, or where turbine housing meets the exhaust manifold; then you have a problem.

or cracked manifold/turbine housings /ubbthreads/images/graemlins/laugh.gif

Boost leaks are found with a BL tester, what kind of turbo setup do you have on car?

 

[iceman69510]

Quite possibly a cracked manifold.

 

[TRBODSM]

PM me and I can help you out if you are not too far.

 

I have a large 16g turbo and just a log manifold right now. Should I pull the heat shield off and start looking for cracks?

 

[524of1000]

I would.

 

Cracks and gaskets both. Especially if it's a 1g manifold

 

so somehow my downpipe came off from where it connects to the rest of my exhaust but I got new bolts and new gaskets. Ill let you know what happens when i finish it all up.

thanks guys

 

Ok so everything went back together smoothly but I still seem to notice odd things about the car. If i pull it out of gear and its at high rpms when they go to steady at an idle the car usually dies. the rpms go so low the car just shuts off or sometimes it will catch itself but barely. what could cause this?

 

[TRBODSM]

Is your BOV recirculated?

 

[Hertz]

Quoting rockvr4:
the rpms go so low the car just shuts off or sometimes it will catch itself but barely. what could cause this?



Your idle/BISS is not set correctly, and/or the speed sensor (reed switch) in the instrument cluster is dead.

 

yeah my bov goes right back into the intake just short of the inlet on the turbo. Could that be effecting something?