Finding Air Leaks In The Intake

[mikel]

Does anyone got any ideas how to locate an intermittent air leak?

I have a pod, FMIC and stock inlet manifold on a R33 GTST.

Occasionally when I put the boot in there'll be a different sound as if I'm sucking air in somewhere.

The issue started after a full day at the track.

It doesn't occur all the time, and after it does it once it disappears again, as if the leak has temporarily sealed itself (ie pipe gets hotter and expands).

I've tightened all the clamps I can get to, and can't identify any split hoses etc. All hoses are the blue silicon ones. There are still numerous clamps I can't reach.

I hate to think what a tuning shop would charge me to locate such a fault.

Does anyone have any ideas on locating these types of leaks?

cheers,

Mike

[nizmo_freek]

Check your PCV valve, it is the little 2 way valve that is pushed into the side of your intake cam cover, it then connects to the intake manifold via a rubber pipe, it is only small, put your ear up to it while the car is idling and if you hear it whisstle then it most likely has a stuffed seal (mine sometimes makes a hissing noise when the car is idling which i have traced to being the PCV valve seal leaking i think) , another way to check for vacuum leaks is to get a long peice of vaccum hose, put it up to your ear then put it werever the whistling noise is coming from, you can hear it very clearly with the vaccum hose. Also while the car is idling you can wriggle the PCV valve around a little bit and see if the hissing goes away or gets worse

Edited February 15, 2007 by nizmo_freek

[RBwhatever]

I've heard you can easily test this by pressurizing the system with an air compressor while your car is off. Apparently it make leaks very easy to locate.

Unfortunately I'm not sure of the procedure.

I also would like to know.

[Craved]

block the intake pipe to the turbo off with a rubber unit- this creates a sealed unit.

in the centre of that end seal, you put a nozzle to insert compressed air, using soapy water spray areas prone to leak, the air escaping causes bubbles

other way is to spray a combustable solution - rp7/wd40/carbie cleaner around, if the revs rise at that time, then there is a leak there.

[2gceffy]

hey guys

i did this just the other day

here's some pic's mate to help you out, i found a tyre tube and just cut out the nozzle and pressed it into the bottom of the bottle..

found one of my blow-by hoses had a split in it, i still have a whisling noice and bad idle so im outta ideas now

VVV for some reason posted twice

Edited February 15, 2007 by 2gceffy

[2gceffy]

hey guys

i did this just the other day

here's some pic's mate to help you out, i found a tyre tube and just cut out the nozzle and pressed it into the bottom of the bottle..

found one of my blow-by hoses had a split in it, i still have a whisling noise and bad idle so im outta ideas now.. my noise is coming from around the blow-by hose that connects to the inlet manifold

in the bottom pic you can see the split i found and the lil metal cylinder with the bolt in the top ( duno what its called) i think thats whats making my whisle noise

hope that helps ya mate

[sky-017]

i notice the same whistling noise after i drive and the car is left to idle . still trying to sus it out - i might now try some of the solutions posted...

[mikel]

Thanks guys - all very helpful

cheers

Mike