White_951

Well...I built the pressure tester last night and did a vacuum test...big leak under the intake manifold...

What I haven't been able to find is how to chase this leak down (if it isn't self evident) once the manifold has been removed????

TIA

Thom

How do you know it's under the manifold?

You may want to check the 90° rubber hose linking the AOS cover with the hard line going to the J-boot. Oil fumes and rubber don't make a happy pairing and it usually ends up cracking, though it's often not noticeable without pinching it with your fingers.

Ben951S

Make yourself a soapy water mixture, and spray that fella over the intake manifold gaskets while it's pressurized. Also, the first response was good too.

Paulyy

once you pull the intake off, you'll easily find the leak. once the intake is off, block every hose that came off the intake and the IC pipe and do what ben said, spray soapy water over the hoses and you'll see bubbles once pressurised, you'll be able to hear the leak anyway

White_951

I sprayed everything I could access above and along side of the manifold, no evident leaks in BOV, J-Boot, hard pipes, dampner, fpr, brakes, heater valve, etc....

I could see the ISV and sprayed the large side hoses also...no bubbles there.....

But with a piece of pvc to my ear I can clearly hear a leak under there....

White_951

Thanks Pauly....

blown 944

Borrow a smoke machine. That is the best way to find leaks imo

alxdgr8

Just use something like this to pressurize ISV/vac lines. It's probably not the manifold if it sounds like it's under the intake.

lee101315

You would really be doing yourself a big favor by ordering all of the vacuum lines/breather hoses new and changing them all at once.

That goes for the intercooler couplings, and turbo inlet and outlet hoses. I had the outlet hose between the turbo and the intercooler hose break on a 5 deg day... definitely not a good day

Its the first thing I do on any 951 I buy or that comes in to me for service. Check the ISV for leaks, test the TPS and make sure it works, and set the idle according to this http://www.lindseyracing.com/LR/Parts/IDLE944T.html and you should be on your way to a good idling 951

Heres the hose kit I usually order http://www.lindseyracing.com/LR/Pors...1-VDK-VHK.html

ehall

You could also have a cracked AOS, or a leak at the hose.

boerge

My throttle body was leaking and it sounded like under the intake, and I didn't actually see it until the smoke machine came on.

chris951

Check the vacuum hose under the throttle body, it's hidden under there. You may also have a leak at the throttle body/intake o-ring interface.

White_951

Yep....throttle body coupling torn! Everything else looks new as advertised by the PO......

Already ordered my stuff from Lart...Thanks all!

chris951

Glad to help

ehall

TOUCHDOWN! Glad ya got it! We all hate vac leaks!