Just replaced air hoses with silicone hose kit as have been suffering with boost issues and wanted to eliminate any deteriorated ones which could be causing boost randomness ie boost fluctuates from drive to drive and I can hear air leak when boosting. So replaced them and now boost is best its ever been but am still hearing a hiss and after hitting full boost the brake pedal feels hard like has lost servo assistance, have checked pipe work to servo and all looks good. Any ideas or has anyone else witnessed this problem?

 

did you replace the hose from brake servo too manifold with silicone hose?

the standard hose has a non return valve in so you still have servo assistance on boost

 

Yes I did replace it, just looked like a normal hose? You saying it has a valve inside original one?

 

Hose I replaced joins the metal pipe which runs across bulk head then goes to servo, only replaced one to the metal pipe. Is still standard from pipe to servo

 

Yes, it has a one way valve inside

 

+1

 

Jeffwrx you legend!!! Just checked pipe and now see valve inset in pipe your talking about. Thanks dude!!

 

Suggest you cut it out rather than try and push it out - last time I did that it broke. Stick the new hose in a jug of boiling water before pushing it in the new hose

 

the valve is a one way valve so make sure you turn it that boost cant go into servo, but you can suck air back from servo... make sense???

 

no problem

 

Yes indeed totally understand, just went out and put standard one back on, not too fussed with silicone equivalent will maybe take valve out at work tomoz. This explains a lot as was hearing boost around pedal area and also smelling fuel like smell when on boost. Hopefully this sorts the lot. Nice one guys, much appreciated.