Hi all,

New to the forums, but have been reading a few posts since we bought a Au1 4ltr 6 cyl about three months ago.

Problem is there is a noisy whistling noise from the engine bay now, and its driving me nuts. I have tried to located the source of the noise and it sounds like its coming from around the area just under the throttle body (which I cleaned along with the IAC)

have replaced so far:

serpentine belt, tensioner pulleys, spark plugs (for rough idle) but to no avail.

Somebody mentioned vacume leak, so I have tried all pipes and all hold a vac ok, so maybe a gasket leak? but would that whistling noise hold in time with engine revs? could the charcol canister make that kind of noise if faulty?

Rough idle I think is a injector seal prob, spraying some carb cleaner around the injectors with engine running smooths out the idle, so changed o rings on first two injectors but still does it, and now spraying carby cleaner does not smooth out the idle.

Any ideas fellas? prob time to go see the proffesionals , so could anybody reccomend a good mech in Perth metro area?

Cheers all.

your first 2 injectors might be blocked causing the rough idle, which is why the carby clean didnt work after you put new o-rings on them.

is your air cleaner all tight

Thanks for the replys guys, yeah the two injectors are prob blocked so they need a proper off car clean to see.

The air cleaner was ok, but I will remove the element and see if that helps, and check the connections

cheers

air con compressor? i know they make strange noises in the au onwards...

Check the intake manifold gasket

Cheers boys,

I will check the intake gasket tomorrow, put a bit of engine oil around it, see what happens.

cheers

I'd say it is a vacuum leak. Is there sort of a depressurizing sound when you turn the car off?

If so then there definitely is a vacuum leak.

phong =P~

It really does sound like a vacuum leak problem, and if it resulting in the idle being rough I would check the map sensor vaccum cable. You could have hit it with the carby cleaner when you were sprayin the injectors

Where is the map sensor vaccum cable located on a 4.0 ED? I'm having a similar sound from my engine at the moment so I might have to check things.....My engine has a set of recently recoed injectors so I know it's not that.

Facing the front of the car, it is on your right(attached to the firewall and behind a wiring loom) just remove the metal clip holding the loom there and two srews (phillps head) and your done,apart from the plug and vaccum line.

It is black and rectangular in shape.

BTW- Don't put oil on the exhaust manifold unless you want a steady stream of burning/ smouldering oil coming from your engine bay.