I was doing a leak test today on my car for the first time. I found a leak coming from this hose circled in red. What hose is this, is this a common leak? Can I take off the factory clamp and use a worm gear one to fix it? Looks hard to get at because it is behind the oil filter housing any tips or tricks?

Thanks!

 

I can't tell which hose that is but I have replaced some of the factory clamps with the worm gear stuff because of boost leaks.

 

Just tried that, It appears like the black plastic Y fitting is leaking and not the actual hose now. So much for the easy fix!

 

I have had several leaks from hoses with factory clamp, used worm clamps also and leak stopped, just don't over tighten.

 

That is not a pressure line Matt. That is a vacuum line providing vacuum to the brake booster in the front of the car. I capped this line off after swapping to the 997GT2 vacuum pump. Hope that helps...

 

Thanks John, If that is the case I must have a bad check valve somewhere I think..

 

the check valve just above the plenum is notorious for cracking. if you can pressure test from the turbo inlet you'll hear it hissing. it'll be that obvious. not sure from the pic its the area you've outlined but air box out, and near the plenum. if it is? change them both same time. cheap insurance, and they commonly go bad.

 

its the black venture valve... replace and do another test

 

Thanks, I have ordered a new one now.

 

How does this work? I have a new Venturi valve and when my var comes on boost for a split second the brake pedal is rock hard, I need to either fit a one way valve or run a separate pump.

 

I would love to hear the story about being on full boost with the brakes on - how does that work?!?!!

 

No rock hard as in no power assistance! Its only for a split second as the car comes on boost.

 

How did you figure that out? I don't see how you can check the brake when your foot is on the gas all the way to the floor. Did you have one foot on the gas and the other on the brake?

 

Ok so you accelerate away from a light and someone steps off the sidewalk!! Now in the UK we use the pedal in the middle (on a 6 speed) to stop! Ive now had 2 996 turbos that do this, its pretty simple, the line going to the servo has a vacuum in it, if it gets pressure you have no power brakes. You may think your being clever but im trying to figure out the solution to a problem here, do you think im making it up? If I accelerate hard and have to suddenly brake sometimes I have a rock hard pedal, its not rocket science.

In fact if your feet cant move fast enough to come off the throttle and brake while still on boost maybe you need to rethink your car or driving style.

 

Ah, OK that kind of explains it... By the time you move your foot from gas to brake, you are no longer at full boost (I guess close maybe). I've never gone full pedal with people that close, so that situation has never presented itself for me. Thanks for explaining it - I'll have to give it a try. I wasn't trying to be a di*k, I just didn't get get how you were getting there.