I noticed a strange noise in the car a while ago now which has gradually got louder over time, to a point now where I struggle to hear the radio. It's very difficult to describe, but it's a sort of reverberating sound which seems to engulf the whole car, as opposed to coming from any 1 particular area.
It's only really noticeable when cruising at a constant speed, and at around 3000rpm in any gear, and at its loudest at over 75mph in 5th. If i drop below 75 it's hardly noticeable, but over 80 and you need to turn the radio up to hear the music! At under 40mph it sounds perfectly normal.
It's not bothered me until now as I've had it regularly serviced and there didn't appear to be any other symptoms, so figured it was just the age of the car making it a little more clunky.
However now that it's got noticeably louder all of a sudden, I figured I needed to get it looked at. But before booking it into the garage I took a look under the bonnet and noticed that a braided tube in the top middle area of the engine bay has become detached. I don't know if this is the cause of the noise problem, or just coincidence. See photos below showing the detached tube ...
Engine bay showing area where fault is: http://www.flickr.com/photos/mikebabs1/889359914
Close up of detached tube: http://www.flickr.com/photos/mikebabs1/889385726
Does anyone know what this tube is and/or the cause of the noise problem I've tried to describe?
Incidentally the car (as per signature) is a 2001 2.0 petrol with 77k on the clock and is yet to have the cam belt done, which I'm also planning on having done in the next week or 2. I initially thought the noise could be the cam belt, but now I'm not sure.
Thanks all in advance.