Loud Shrill Noise at high speeds

[inca]

Hi

I am new to the club having recently bought a 2001 XKR and this is my first use of the technical forum.

I would really appreciate some advice on a problem I have with my XKR -when I am driving at high speed (100mph +) on full throttle as well as when coming off the throttle I get a very loud shrill noise which I think is coming from the engine bay area. I thought it could be wind noise but having done it again recently I am more convinced it is coming from the engine bay.

I took the car back to my Jag dealer who replaced the main belt and supercharge belt (to rectify a different fault - a chirping noise I was getting at tick over whilst the engine warms up) but we were hoping it might also fix the shrill noise at high speed - but it hasn't!

Any help on this would be great.

Regards

Mark

[Nik]

Hi Mark ,
Could this simply be the sound of the supercharger working hard , if thats the case its normal ............... unless the supercharger bearings need replacing ,

Nik

[inca]

Thanks again Nik. The jag Dealer replaced the supercharge belt so I guess they would have noticed/checked the bearings at the time they did the work? Beginning to think I may have given a poor description of the noise....! It's a loud high pitched noise like air apssing through a very thin slit.. It occurs when I am backing off on the throttle as well as at full throttle so would it still be the supercharger working hard? Is there anything else mechanical it could be?

[jagtech]

Hi Sounds to me like a wind noise try plugging all vents / holes around engine bay to see if it stops