High pitched noise

[michaelg]

Noticed a high pitched noise for about 10 mins on the motorway today, seemed to be emanating from the rear of the van , Does the DPF regeneration make noise ? no idea what else it could have been.

[oilyrag]

If it does it again you could try easing the handbrake on and see if the noise changes and be brake related, and also dipping the clutch and coasting, in order to narrow down the source.
Not roof aerial ?

[michaelg]

Thanks mate , will try to narrow it down when i hear it again driving.

I've also noticed another different hi-pitched sound immediately after i switch off the engine for about 10 seconds , Its only with the bonnet up that it can it be heard.
Seems to be coming more from the belt/left side of the engine, could be air de-pressurizing perhaps ?

[Tree]

mine makes a high pitched sort of beeping noise when I turn off the engine - pretty sure its the fuel rail depressurizing or something similar

[michaelg]

Noise started again last night for about 2 minutes, lightly applying the foot brake stops the sound immediately, debris caught between the disc pad maybe?

[oilyrag]

As the sound is possibly from the rear it may be a build up of dust in the drums, assuming you have drums, and this is not difficult to remedy. Take off the drums and use a wet type brake cleaner - stops you filling your lungs with dust - check all is OK and that handbrake cables aren't dragging.
If disc related then it's a pad just touching the disc face and vibrating. If so, take out the pads, clean everything and put some copper grease on the back of the pad where it touches the brake piston.
More likely to be annoying rather than trouble. You may even have a small piece of grit caught in the caliper.
Probably stops when it rains, which is fortunate for those of us in Ireland!

[ron]

Champfering the leading edge of the pads helps as well.