Whirring noise at idle

[Kinks]

Had a strange noise start to show itself.. at idle I get a pronounced whirring noise which sounds like it's coming from the top of my engine. Seems loudest above the cam covers and only does it at idle, at higher RPM it goes quiet. Also only happens when the engine is up to temp, I think. Will have to check next cold start.

It definitely seems to be loudest above the engine, rather than at the front.. so I wouldn't think it would be any of the external belts (alternator etc). The engine's done 118k and the timing belt was done at 100k by the prev owner.

Any ideas? I'll try and grab some hose and do a bit of listening to see where it's coming from but I should probably take it to someone to find out what's going on. Suggestions would be helpful

[Damo]

I have a similar noise to what u have described but it is from the clutch. It goes away when u depress the clutch pedal. Have u tried this yet?

Otherwise I have no idea on what it may be.

[MegaGTS4]

Injectors maybe?

MEGA

[Guest RedLineGTR]

idler bearing or something to do with the cambelt..??

[Kinks]

It's not the clutch, it's not the injectors it's coming from the front of the motor.

Took it to a mech who agreed and said it could be the cam belt, could be the idler bearing. Also had someone else suggest water pump. But it is a belt/bearing noise IMO. Either way it doesn't look like it's possible to diagnose without pulling everything apart, and that won't happen before christmas...

[Damo]

Well good luck with it all

[Craved]

what about the viscous fan? have a feeling mine might be playing up because when i shut the engine off it winds down, never noticed it before!!

[Kinks]

Winds down? Mine will spin for a few second after the engine has stopped, that's normal unless the clutch is engaged in which case it should stop instantly.

It's not coming from the fan belt or clutch fan region, sounds like the front of the block, and if you listen closely it sounds like the noise is coming out from underneath the timing belt cover.

[Genesis®]

a mate of mine had the same problem with his R33 GTS. The sound stopped once the cambelt was changed.

if it is really the cambelt, get it changed ASAP before it causes greater damage.

[DJ984]

I have the clutch problem to...(like Damo)... any idea what this is?....

[rb25]

Mine does exactly what Damo's does and most other's do, just the gearbox turning over/clutch.... hope thats all it is.

-rb25

[blind_elk]

Mine does exactly what Damo's does and most other's do, just the gearbox turning over/clutch.... hope thats all it is.

-rb25

It's usually the thrust bearing (the bit that actually presses on the fingers of the pressure plate). In my experience it's not a critical, must-fix, sound.

[BIGBLOCKR31COUPE]

Try the old screwdriver stethiscope trick(tip against part & handle to ear). You may find that it is just the aircon belt idler pulley. This is quite common and can sound like it is coming from somewhere else. Once you have listened through a screwdriver you should be able to pinpoint the noise easily.

[Kinks]

cheers, i will try it.. hopefully it's coming from somewhere trivially nonimportant like the air con pulleys.. which isn't even gassed so I should probably just remove the belt if that's what it is lol.