Hope you can help....

Our X reg Fabia 1.9Tdi Comfort AC (89k miles) has developed a high pitched tuning fork / whistle / humming noise.

It occurs when the car is travelling between 20-70 mph, when cold or at normal operating temperature & does not increase in volume. There is no performance loss. It occurs once or twice on a journey of approx 40 miles, but not everytime you drive the car....The air con & radio are turned off.

When I push the clutch down it stops, again returning when lifted.

It did it once or twice about two years ago, but over the last week it happened everyday. The clutch thrust release bearing started chattering a while after we bought it almost 4 yrs ago, but was not replaced as the Skoda warranty did not cover it. Could this be about to break?

Any ideas on the possible cause / remedy /repair costs if it goes bang?

Thanks for your help!

can't see it being the clutch release bearing, for one it would make the noise whilst stationary

odd that the noise doesn't change when the speed increases, but this rules out wheel bearings etc

anybody else got a theory ?

No pitch increase but stops when clutch pressed down, suggests it's engine load related. My money would be on vacuum control block, or EGR valve. It could also be the clutch release bearing rattling due to free play in bearing, the action of depressing the clutch loads the bearing and stops the noise.

i bet it's the ac compressor, the one on my fabia always made funny high pitched noises

Thanks for the quick replies, I'll see what happens....