most of the pressure should stop at the throttle body. what little gets by won't make a difference. You can tell the difference if it is leaking into the engine or leaking to atmoshpere....louder hiss...

 

hey Mike, if i can remember correctly: a buddy of mine did it a while back for me, and alot of the air was going thru the engine, so i think he cranked the motor a bit until it stopped leaking... (turned the crank from pulley)

 

I guess it wouldn't hurt to "bump the key"...I would think if you had a leak it would be obvious enough to hear it without having to do that, but I guess it is possible.

 

Hers is a very well made kit and not too expensive..

http://www.boostpro.net/prodtester.html

 

I should have all the parts to do the boost pressure leak test today.

I only have one question. How do i make sure the valves are closed, and the air just doesn't go straight through?

 

Air should stop at the throttle body?

 

Wouldn't 20-30psi force it open?

 

PM sent!

 

Didn't force mine open.

 

Sent PM originally but thought this might be good knowledge for the 6'ers. I had the same code come up on a CEL. I took it to my local Porsche Tech and he said he's never seen that code before as it was rare. I am getting ready to change my MAF sensor and see if that fixes the CEL. It has been in intermittent problem, but annoying. The Tech never said anything about checking for a Boost leak. Attached is the sheet with the factory recommended tests & possible fixes for the problem...

 

I am now getting psm/abs lights occasionally... I didn't get a chance to do the leak test, they sent the wrong size, will need to purchase different reducer.

Has anything seen a Hitachi Maf go bad?

 

Hey, I changed my MAF and my car is running better and there's no soot on the tail pipes and best of all no CEL so far!

 

What MAF are you running?

 

Stock... my set up is K24/18g's, 5 bar FPR, Protomotive tune. What kind of set up do you have?

 

Figured I'd post a quick update to this thread as it seems to be a common enough issue for those running the Hitachi MAF - Thanks to Thomas for helping me find a boost leak, all is well at the moment sans CEL. Here is a PM correspondence and quick break down of my (fingers crossed) solved issue:

Are you getting the 0175 code solo? I was getting EXACTLY the same codes you were/are - P1109 sometimes in conjuntion with 175;172 but not always. Running the basically the same kit, Evo tuning, Hitachi MAF, etc...

I knew the O2's were good so I didn't replace them but it was time to do plugs anyways so I swapped them and another MAF that I had laying around to make sure it wasn't actually bad - all was well for about 2 weeks and I got the light again - read it down and had all three codes. After scratching my head (Still not quite sure how a boost leak is causing an idle error issue) I read your thread and searched for a boost leak - found one coming off the passenger side Turbo, fixed it cleared the codes and am now hoping not to see a CEL for awhile. That was just a couple days ago so even if that wasn't the solution it'll probably be a couple more days before I get the light back. If that's not it my intake plenum throttle body and idle control are getting a thorough cleaning although hopefully this will have already fixed it. Let me know if you're still getting the 175/172 codes on their own now (bank 1/bank 2)

- Another side note, this car is driven up and down a half-mile gravel driveway a few times a week so I wouldn't be surprised to find dirt is an eventual issue.

+1 Rep to Thomas for the help.