1.8 Bravo - noise in air intake?

[Hellraiser]

My Bravo's got a weird problem - on tick over you can hear a sound like someone blowing over the top of an empty milk bottle. Followed the noise back thru the air filter, if I disconnect the idle control valve the noise stops and the engine idle drops slightly. Turn off the ignition, reconnect the ICV and it starts again. Any idea why this is happening? Surely the ICV can't make that much noise?

Hellraiser........>

 

[sven]

Not sure, but can be:
leek in the air intake system-check the connections of the hoses & tighten the hose holders

the idle control valve needs tightening or is faulty-take it out and spray some lubricant on it. he can be rubbing its self

Just my opinion-not sure.
PS-try FAO Tom on the subject

Sven

 

[Tom]

Just to keep you happy

Yes they can make that much noise, the hole is very small so the air moves quite quickly making the noise. You can year the valve openning and closing on my 1.6 quite clearly.

 

[Hellraiser]

Cool, so just squirting some lube in (WD40 or similar) should sort it and not damage anything else?

Cheers

Hellraiser.........>

 

[Tom]

The noise is the air rushing through the valve, no way to stop it.

 

[Hellraiser]

It's intermittent though, sometimes it is perfectly fine yet other times there's this "milk bottle" sort of noise going on. The noise it's producing at the moment is definitely not the noise it normally produces!

Hellraiser........>

 

[Tom]

Worse when its cold?

 

[Hellraiser]

Makes no difference, seems as likely to make the noise after a motorway run as from first start in the morning. It's reached the point now where it's becoming constant - you can actually feel the vibration thru the airbox.

Hellraiser.........>

 

[Tom]

Could be some crap in the valve.

 

[Hellraiser]

I'll give it a blast with WD40 in my lunch break tomorrow, see if that helps.

Cheers all

Hellraiser........>