vacuum leak issue

[superDorifto]

whats up guys? I know that this technicaly belongs in the KA forum, but Ive come to respect the KA-T forum a lot more and i think you all might have a little more advise to offer when it comes to finding a vaccum/boost leak. The motor that Fiz helped me put in my zenki last week is running stong, got nearly 500 miles on it already with now leaks, or overheating issues. the motor was rebuilt, and it came from an s13, it now resides in my s14. When we first started the car up and started to time the motor you could hear a distinct whistling sound coming from the intake manifold. the car refuses to hold its own idle for more that a few seconds. the revs just drop until the motor stalls out. ive taken the intake manifold off twice looking for a cracked hose or a leaky gasket, and ive come up empty. its a very difuse sounding leak, and i cant seem to isolate it, honestly it sounds like its coming from the injectors, but that doesnt make any sense. any help or insight would be apreciated before i tear into the manifold again.

[Craving4Boost]

if it doesnt even let you idle..it must be a big vaccuum leak. what does your boost gauge read? i know the only vacuum leak that caused my idle to just die is the EGR. are you using a any rtv to sealing the EGR block off plate? try pushing the plate down HARD while idling and see if it helps. worked for me....hope it works for you

[virus77]

you can make the boost leak tester from the stickys in the kat forum and just hook it up directly to the throttle body of the car, it will find leaks in the manifold.

[fiznat]

Dude I think we're going to have to just redo that whole intake mani over again. The leak has gotta be coming from somewhere stupid in there, and we're never going to find it unless we pull the thing apart.

Another thing I thought of tonight-- if you can get your car to idle for 10 seconds on its own... see if squeezing shut the IACV vacuum hose (coming off of the intake pipe) effects the idle at all. If everything was working properly, squeezing that hose SHOULD shut the car off. If it keeps running with that hose pinched then its getting idle air from some other place (I.E. an IM leak)

Come over and we'll look at it tomorrow. Also gotta get my freakin stereo working.

[superDorifto]

yeah, were gonna have to tear the whole thing apart...i just wanted some other people's opinions and past experiences as to where it might be leaking from.

[superDorifto]

found the problem. Turns out that the loud whistling noise is caused when the pcv valve vacuum line developes a leak, or in my case is not connected at all. Fiznat and i buttoned the intake back together and the car settled right into a nice idle at 750rpms....

[Craving4Boost]

damn vacuum leaks...they always screw everything up...