Need help please very annoying problem

[nissan ka24det]

hey guys im pretty new here but i have a 350z with fujita cold air and denso full cat back. and tein suspension and after all the installation now when i turn the car off in the engine bay from the left there is a loud hissing noise. i have now idea what it is but very annoying. the sound is right in between the top left timing cover and the bottom left plenum. please must get help. and ideas would be great thanks guys.

[joe603]

Make sure everything is tight...did you do the plenum spacer install? You might have pinched the front rubber oil fill (i did it on my G35).

Check all vacuum lines.

It could just be the intake noise though...

[nissan ka24det]

yes i did do the plenum spacer then forgot the spacer then cracked the manifold then bought a new one and did it all over again. and all of the hoses are tight but i scaned it and it has a slight v/l i dont know from where and the fujita intake makes a little noise but thats not it. plus the o2 sensor slightly moves from rich to lean. my best guess is the egr valve if possible. might be a stupid idea but ill keep checking i mean i tried smoking the thing but my fogger only does 10 psi but the scanner shows that its a 24 psi leak so i need a bigger sun fogger. still need help thanks.

[evildky]

wow your running 24 psi of boost?!

guessing you mean 24 in/lbs of vac?

[nissan ka24det]

you are absolutly right but its kinda the same for the same thanks for the correction though. but do you have any ideas man i cant get this this i feel like i need just a little info lol thank guys for all your help though.

[evildky]

first of all, your a/f meter, means nothing not usefull unless your playing with the engine managment or forced inductiona dn even then useless unless its wideband

second, your "scanner" shows a leak?

third, your fogger? so you have some sort of smoke machine that pumps smoke into the intake with the engine off and the intake sealed up and it also presurazes the manifold to 10 psi?

4th, I realy don't know why you even bothered to mention what brand of suspension you have for diagnosing an engine noise?

sorry if I come across as a ball breaker that isn't my intent, it's just that if you have a legitimate problem we need as much pertinant info as possible and the stuff thts completely unrelated sush as your suspension you should leave out

and for the sake of argument we'll assume you have checked all your hoses and topped off your coolant

now does this hiss present when the car idles? is there any drivability issues? does it make the noise if your not using climate control before shutting down? could the noise simply be the freon passing through the system as you shut the car off?