Hi everyone. I'm new to the site so sorry if this has already been answered. I have searched and can't seem to find anything to pin this down.

I've had my 2011 Greenline diesel for nearly a year now and for the past few months it's been been making a really annoying noise that I can only describe as clhirping like a cricket!!

I can only hear it inside the car, it seems to be coming from the front offside and I can't connect it to anything in particular. It only lasts a few secconds and happens randomly while driving and when idling. Performance, handling and fuel consumption are all fine but I'm wondering if something is going to suddenly pack in.

Could it be something to do with the DPF regenerating?

Any help greatly appreciated.

A noise like that is likely coming from the auxiliary belt, possibly the tensioner or alternator pulley.

Thanks for the quick reply sepulchrave! It's going in for a service and MOT next month so I'll ask him to have a look at that.

In the meantime I'll just use the old trick of turning the radio up!

Cheers!

A DPF regen noise would last for quite a few miles. On my 1.4TDI Greenline the engine noise deepens when doing a regen and is quite noticeable. 

The noise will most likely be initial failure of the alternator pulley sprag clutch or the aircon pulley shear plate.

 

Try switching the aircon off to see if the noise changes or disappears.

 

Mine has started making the noise, its the AC pulley I think, its working OK and the high & low side pressures are what they should be but putting an inspection mirror down in front of the pulley reveals some oxidised metal dust, the noise is not apparent with the AC on, as the shear plate rivets & straps look OK & the pulley boss & splines are aluminium perhaps its just a characteristic!

Thanks for the pointers guys.

Re the air con: I hardly ever use it - usually just to clear the windscreen in winter and the noise is happening whether it's on or off.

I'll try leaving it on for a while and see if it makes any difference.

I'm just glad it's nothing to do with the DPF. I was quoted £1,500 for a new exhaust last year (dealer only part inc DPF and cat) so I ended up just having a section replaced which meant removing a sensor and refitting it in the new section.  I thought that might have caused problems.

I've got a really good mechanic I've been taking my cars to for years. I'll tell him what you said and get him to look at it. I'll let you know what he finds.

Cheers.