Air filter whining?

[rusgb]

Hi all, another question which has been bugging me. My Chimaera has been whining quite a bit. I suppose the sound is that of a distant vacuum cleaner... It seems to start when the car has warmed up a bit. The local garage took a look and we couldn't really work out where the noise was coming from. It seemed to be from the air filter in the nose, but the sound was then probably being amplified on the way up to the plenium, so it seems to come from no clear locations

I have made a video if anyone thinks they may recognise the noise:
http://www.youtube.com/watch?v=RdlswyVJE3I

The performance seems unaffected and the noise disappears at about 2,000 rpm for obvious reasons!

Any thoughts are (as always) met with a cheery smile, Rus

[drlloyd]

I have heard a lot of Chimaera's that make that slight whining sound from the air filter / induction pipe around idle. Not sure exactly why but just assuring you that it is normal!

[Lesliehedley]

Could it be this:

http://www.pistonheads.co.uk/gassing/topic.asp?h=0... the AFM&mid=18551

[Tasmindevil]

Talk about spooky, just back in from the garage and my wedge (5 litre Griff engine)has developed exactly the same noise and same location, in fact listening to the youtube video its absolutely spot on. I tried using a hose to my ear to pin point it but still unsure, it does not seem to be from the AFM as I removed the air filter so current thoughts are power steering pump/belt or possible from the top of the radiator as I recently fitted a new top pipe.
Hopefully I will get back into the garage Sunday and go through a process to pin point the noise.
The wonders of PH huh
Good luck
Cheers
Hamish

[redeye]

t hink you will find this is called the engine noise of a chim ,or the golf clubs wanting to get out of the boot . get a cerbera
sorry could not resist

there maybe trouble a head

Edited by redeye on Friday 17th September 10:00

[JKY]

Turn the air bleed screw out (also known as base idle screw) - this is where the noise comes from and is then amplified down the air trunking. Had exactly this on my griffith.
It too was difficult to pinpoint and sounded like a bearing, belt etc but in the end was simply the air screw. The reason that it gets louder once it has warmed up is that prior to then the stepper motor is letting the majority of the air through which bypasses the air bleed screw.

Winding this out a turn or so should not have any effect on the idle. The stepper motor controls the idle on these cars, the base idle screw is merely that, base idle, and only causes issues if it is so far out that it exceeds the limits of the stepper motor movement. A poor stepper motor is usually the cause of most idle issues and is very frequently overlooked.

Edited by JKY on Friday 17th September 11:28