I have a reverb \ resonance sound which I can replicate which appears to come from the NSF side of the vehicle.

At motorway speeds it is a constant vibration \ resonance and appears to be engine related, accelerator down it gets louder, but take foot off and it is still there but not as loud.

I can also replicate this sound and get a brrrrp, sound from the NSF if the car is low down in the rev range, 4th gear, 40mph, 2000rpm, or 3rd gear 30mph, 2000rpm and the sound only lasts for the revs to rise and then brrrp is gone, but the resonance is still present.

Long journeys are now a torture.

It sounds like a wheel bearing, but have checked this and also when I had 4 new tyres the other day asked them to check and nothing wrong with wheel bearing and also doesn't link in with the other description of the fault anyway.

One of the breather pipes was noted on my last service as being frayed. The frayed end was cut off, so this pipe is now shorter than it would otherwise be, could it be related to this? It also had Cambelt \ water pump around the same time this sound was apparent.

Any ideas people any help massively appreciated.

This might sound "off the wall", but check the somewhat weak centre and front brackets for the rather hefty exhaust system.

It could be a loose heatshield. The noise is related to engine speed so you can rule out the running gear.

You should be able to reproduce the noise when the car is not moving. Go under the car and get someone to VERY slowly increase the engine RPM until it makes the noise

Having done a bit more research and testing, listening I think it may be to do with or related to one of these others posts

http://briskoda.net/forums/topic/162689-turbo-manifold-gasket/

http://briskoda.net/forums/topic/158611-manifold-gasket-screws-tightened-now-a-metallic-vibration/

http://briskoda.net/forums/topic/190998-low-rpm-unknown-mechanical-noise/

I have noticed that there appear to be 2 sounds which may or may not be related and need your help in further analysis.

Sound one is the brrrrpp which is heard when using the torque of the engine low rpm 2000-2500 going up a gradiant this doesn't last long.

The other sound is a more tinny rattle which can be heard as a constant noise which may also be causing a very annoying vibration reverb which can be felt and is quite noticible from 2500-3000 maybe higher. This tinny noise and vibration also seems to be revs related as I can drop the clutch with the car moving along and the reverb \ tinny noise will disappear.

The noise tinny vibration sounds like it comes from the back of the engine bay under the windscreen and with someone revving the engine around 3000rpm it sounds like there may also be some excessive air around that area also.

Any additional help and suggestions would be greatly appreciated.

Engine mount?

Does the 'brrrrpp' occur immediately after changing gear?

What engine does this car have?

Does the 'brrrrpp' occur immediately after changing gear?

What engine does this car have?

It is a 54 plate VRS with an AUQ engine.

The brrrrp happens within the same gear, it it just whilst the engine is under load during passing through that rev range.