samcowrx

need some assistance please, i have just bolted my inlet manifold back on after refurbing it, here is a long shot, i seem to have an air leak, i see it being one of two things, it is coming from down near where the inlet manifold bolts to the heads on the passenger side, most prominant slight whistling sound on start up, when giving a blip on the throttle, and when switching the engine off. there is a hiss on normal tickover, when i took the inlet manifold off to refurb it, obviously the fuel rails had to come off, there are seals which are positioned in the inlet manifold for the injector cups on the rails to sit in, (if that makes sense?!), could the one in the local area possibly be leaking? I was as sure as possible that i made sure the cups sat in the rubber seals as straight and as tight as they should, would fuel leak from here if that is the problem, the other thing is that i fitting manifold insulators, with oe gaskets either side of them, maybe it could be leaking there?, i have bolted the inlet down well but still leaking, is there anything i can do before stripping it down again!

merlin24

iTrader: (1)

Is the engine running rough on tickover ??
If the idle is steady, dont think it would be an air/vaccum leak from the inlet manifold TBH.

cushti

iTrader: (7)

Try this but only when engine is stone cold.

Start it up & spray WD40 in small one-off bursts around the places where you think you hear the manifold leaking. If the hissing quietens down on one particular burst & it runs normal for a second then that's where the leak is located.

(if you don't have any WD40 then do what they do to check for tyre punctures - spray little bursts of diluted washing up liquid around the area & look for the bubbles!).

It could be one of many things - perhaps one of the bolts was tightened too much & has cracked an insulator, as it's pass. side did you recheck the fuel vent pipe was connected back properly & checked the hose for any cracking, have the fmic/tmic hosing clips all been tightened up (I've missed the odd one out in my time), did you use new gaskets on top & bottom of the insulators e.t.c.

samcowrx

it idles correctly hot and cold, i dont think i have cracked the insulator but that would be worth checking, if i was cracked would it still idle correctly?

samcowrx

I did use 4 new oe gaskets on the insulators, the fuel vent pipe has a one way valve on it, venting into the bay, this is not making the noise, i can here a hiss from the problematic area on tickover.

samcowrx

any ideas?

samcowrx

bump

scoobynewbie72

iTrader: (1)

have u searched for leaks with the soapy water method?

merlin24

iTrader: (1)

Brake Servo hose connection ??

samcowrx

Two good posts thanks, i will have a quick look over in the morning, in the light!, search for anything obvious again, then try the soapy water method, i will also have a look at the servo hose, thanks merlin.

samcowrx

You were right merlin, i had to change the hose from the hard pipe on the bulkhead ( from servo) to the IM, i needed it a bit longer, as the raised IM and fmic pipework was rendering the oe hose too short, i just didnt clamp up the jubilee enough on the IM boss!, where it was leaking was not where you could here it leaking if you know what i mean, it seemed as if the hose was 'throwing' the sound down so that it sounded like it was coming the from where the IM bolts to the head.

merlin24

iTrader: (1)

Glad you managed to track the problem down and a simple fix

Mick