Diagram for you.

 

I wasn't meaning it to flame you sorry. Obviously air still gets into the IM. Or you car wouldn't idle point is your cutting back a lot of air gettin in fast not having the TP open. You can only get 2psi into the car air is not blowing past both valves no way.

I have also never put any turbo car to TDC before doing a boost leak test.

 

Thank you.

Turning the engine until two cylinders are at TDC is not the way to conduct a pressure test. One of those two will be at overlap, and that means both intake and exhaust valves will be open. That creates a big leak. The best position for the engine is with #1 at 90 deg from TDC.

At that point, the most substantial leak is across the throttle plate depending upon the IAC stepper position at shutoff.

 

You hit it right on the ****ing nose bro... thanks. Problem solved. Big thanks Bryan.

LOL@people who don't think we know how to do a boost leak test.

 

Glad that was it. I've done so many boost leak tests its recockulious.

 

i didnt even think of the EGR. Good catch!

 

if im not mistaken when u do a boost leak test arent u supposed to plug the lines going to the wastegate to prevent it from opening??? just my 0.02 not a "guru" like a lot of u peepz on here but i know a fair amount about cars...

 

so have i... just never experienced this particular problem... its the first time ive EVER run into the line off... let alont ON BOTH CARS LoL!!! so thanks again!!!

 

i know this thread is old, but i ran into this problem while doing a boost leak test and i wouldve NEVER thought to look back there if i had not seen this thread a few days prior

i just wanna say thanks to the contributors of this thread

 

im having a similar problem right now. ive checked everything, and it will only build pressure to 6 psi. i can hear it hissing out near the stock BOV... but it should be holding much more than 6psi. if its not the BOV, its right below, but everything seems tight and i cant feel anything. bummer

 

Did you check the EGR valve as suggested?

If it's not that, do this:

1. Get some soapy water in a spray bottle
2. Start the boost leak test
3. Spray soapy water where you hear the hiss
4. Look for bubbles
5. ???
6. Profit!!!

 

Thanks for the tip I had the same issue with the boost leak test building no pressure and the egr hose was the problem!

 

Exactly. Turn the crank to TDC. THEN boost leak check it.

 

That won't make any difference.

 

As Ted said, that won't make a difference, LOL.

If one cylinder is at top dead, you will have another on overlap anyway, haha.
Just need a compressor to overcome the escaping air.