Why is my Focus making a screeching noise?

My Ford Focus has covered 76,000 miles, but has started making a slight whistling/screeching noise when I start the car in the morning. If you pull up next to a wall/hedge or go through a tunnel it rebounds back into the car and you can hear it clearly with the window down. I'm worried something bad is about to go wrong. I'll obviously take it to a garage ASAP but hoped someone could give me an idea as to what might be wrong. Timing belt maybe?
Probably a timing belt jockey pulley or tensioner pulley. The other possibilities are alternator or waterpump. At 76,000 miles it is due for a timing belt change, so if you have that done, make sure they change the tensioners, all small pulleys and the waterpump.
Answered by Honest John on

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