Understood. The ironic part is the leak developed after an install by a shop of Markski's 911 tuning inlet. Maybe the check valve got disturbed or just coincidence it just went bad at the same time. Regardless, I have been on the quest to find this leak lol. I replaced my diverter valves already thinking they were bad, but after a quick finger test of the old diverter valves 710N's I knew they weren't the culprit. Hoping its this 16 check valve and I can move onto better things like chasing down Vettes and GTR's

 

Once you pressure up the system take a length of vacuum tubing and use it like a stethoscope. You can pin point the exact location of leaks with some practice and checking.
When check valve #16 is broke though and you remove that hard hose off the turbo intake on the driver's side the air is just blowing out and you can feel it with your hand. Other leaks are generally much smaller.
Or best case find a friend with a smoke machine pressure tester. Those are life savers.

 

Your assistance is greatly appreciated. I will try this and get back to everyone.

 

you'll get it. we all do sooner or later. wish this thread was here when i first looked at it sideways for a few days lol. GL.

 

Yep, sounds like it's the #16. I know they have some in Stock in Atlanta. Like MalcomV8 said disconnect the small black hard pipe that's on the inlet hose before the turbo and see if air is coming out when you pressure test it. If it is then your #16 is bad.

 

Thanks. I will confirm tonight and report back.

 

As you advised, I boost pressure tested again with hard plastic hose off. NO air seems to be coming from it so I reinstalled. I did however take a garden hose (told to do by Marski and another member here) and stuck it into my inlet. I took the hose and channeled it through the first side pipe inside the inlet that seems to route to the F pipe. Air is definetly passing from that pipe. I place my hand inside that pipe and can block off the air. Am I chasing something that maybe normal? Any advise would be greatly appreciated. Attached is a pic. Look immediately to the right- that tunnel is where I feel and hear the air coming into the inlet from.

I also have a brand new set of Forge diverters and Forge F pipe sent to me by Sam last week. Didn't fix the problem but figured I might as well use them

 

You know I could hear some air coming out my inlet pipe too so that may be normal. I was confirming on the pressure gauge that it was holding pressure once I removed the air compressor so deemed it OK.

 

FOUND AND FIXED BOOST LEAK THANKS TO MARKSKI! I owe the world to Mark. Up late with me on a Sunday while he was at the dinner table this man literally walked me through every possible issue. Thanks to picture sharing back and fourth we were able to pinpoint the problem. Basically the shop that installed my inlet crossed two hoses. The one that that runs from bottom of solenoid under diverter valves and the one that runs from left of throttle body. Mark really knows these cars and his reputation shows his experience. Lots of people tried to help me locate this boost leak and he found it. The guy is amazing at his craft and really really knows these cars. It's a great feeling knowing that we have him in the Porsche community and he's always there to help. Thanks again Mark! You're the man!!!!

 

Thanks for the kind words. I knew it was going to be something simple just needed to isolate it. Glad you fixed it.

 

Couldn't do it without you! Thanks again you saved me a lot of time and money! Your inlet is a great power adder and can't wait to put the car back together.

 

Curious, what is the symptoms of a bad #16 valve? Thx..

 

when mine was found to be cracked, it was suspected as there was a minor vac leak and once we pressure tested from the turbo's checking all hoses etc, and working our way diagnostically up the intake, the #16 was about as far as you can go near the plenum. once there, the air escaping could easily be heard.

it's cheap brittle plastic and.. well you know the rest.

 

Cool. Thx. I was just curious what effect that valve has (when leaking) on the operation of the engine. Obviously if the #16 check valve is stuck open, you will have a slight boost leak as a result of it. If stuck closed, it should not really effect anything from a performance standpoint (but will have a negative effect from an emissions standpoint?)

What is the actual reason for the #16 check valve there? I gather that at idle, it allows fuel vapors from the EVAP canister to be sucked in thought the valve and into the throttle body (which is creating vacuum at idle) to be burned by the engine. When on boost, the valve is naturally closed and fuel vapors will get sucked in though line #19 which connects to the intake just ahead of the drives side turbo. On boost the pre turbo intake will have vacuum which will provide sucking action through line #19.

The reason I ask this is that I believe I have a faulty EVAP purge valve (#14) which is tripping the P0444 code. Since getting the P0444 code, my hot idle has been a bit erratic also. On hot engine start up, it has actually stalled a couple of times and struggled to settle into a smooth idle. Curious how all this may be related. I will be changing the #14 purge valve and may change #16 also since it's right there. I was just curious if anyone actually understands or can explain the workings and reason for the #16 or #14 valves with any kind of certainty. My assumption above is based purely on looking at the diagrams.

Smart guys, chime on in please...



[url=https://flic.kr/p/SXvZXB]

 

all i ever looked for, to make the determination the #16 was bad, was search for the leak. so for me, the symptoms were just that. a vac leak, resulting, mainly in boost loss, which certainly makes sense given it's a component of the intake, no? so yeah, i guess "vac leak = boost loss" were the actual "symptoms.

mine ( afaik? ) wasn't "stuck" per se, but rather just hairline "cracked" and did in fact result in loss of power/boost as i've said..

now, that ? i have no idea lol

but gl with finding the problem, as i'm sure you will. still, it amazes me sometimes the number of little things that can plague the smooth and optimal daily running of these cars, that often escape proper identification for so long!

but i do know when to "take my leave" ha.