Boost leak at 10psi

[Country_GU]

Hey all,

Haven't been on in a while, last weekend whilst towing my motorbike out to cooyar I heard this strange hissing sound coming from under the bonnet, checked all the obvious boost/vacuum lines, intercooler piping and boost gauge line, no avail. It only happens around 10psi and above and has a mad almost tyre deflating hiss under load, only over 10 psi, anything under is quiet. I figured it could possibly be the egr but I'm unsure..... The intercooler piping is looking pretty crap as it is (done nearly 400,000 between 3 engines) so I'm gonna replace it along with some vacuum lines.

So my questions are:
1. Where could the leak be coming from?
2. Does anyone know if anyone sells a intercooler silicone hose kit?
3. Where are ALL the vacuum lines? (I've found turbo, ebc, one that hides up the back of the intercooler) AND
4. Will the aftermarket cruise control have a boost line? (A little random but there's a boost line that goes over to the drivers side to a module which I have nfi what it is)

Cheers all

[threedogs]

Vacuum solenoid is next to air cleaner box, that line that goes to drivers side is to Vacuum pump from memory.
Is the exhaust in good nick behind the Turbo, mine cracked there but more a "pit too" sound.
I've only changed one hose to silicon, expensive bloody stuff, You may want to blank off EGR if not done already.
Yours has probably got a vacuum canister under the engine cover too. You may want to think about fitting NADS.?

[Country_GU]

Yeah I'm fitting nads slowly, the Dawes valve and needle are going to be the hardest I think. Out of curiosity what size is the pcv pipe? 3/8"?

[threedogs]

PCV pipe ??? not with you one that one

[YNOT]

PCV pipe ??? not with you one that one

What size hose to fit the PCV filter?

[Country_GU]

Yeah there's a pipe that goes from the pcv valve to the air inlet

[Country_GU]

Anyway I've redone the intake manifold/throttle body gasket, replaced 2 pipes with silicone replacements and secured all pipes with proper t bolt intercooler clamps, but yet there's still a whistle, starts low pitched at around 6 psi then gradually gets louder til 10 psi where it peaks. I lost for ideas, anyone else got any?

[threedogs]

Turbo's do whistle as they spin so fast. Those clamps are great too,
Your boost is low , I take it you haven't fitted the DAWES valve yet.
You're getting there, try to do one thing at a time that way you'll know
what it is. Do you think the EGR pipe could be split and hissing under pressure.
You could easily dismiss this by fitting an EGR blanking plate, one less thing

Was a thread recently where noise increased after engine warmed up
is the noise consistant with REVs

[Country_GU]

It's weird, it happens with the turbo pressure, not engine revs ( be leaning to exhaust leak), I have an auto so it does weird sh!t. It could be an egr problem but at the exhaust end not the intake end at a guess..... How hard is it to remove both end of the egr system on the non crd ones, cause the crd ones are hella annoying

[Robo]

can you simulate the whistle manually?.
maybe try leaning over the engine and poor/spray " Hot " water over sus connections and listen for bubbles/spattering.