Ford Focus 1.8TDCi registered Jan 2005. I get a squealing noise on start up that may last a minute or so then disappears. This is most noticeable when weather conditions are damp/wet and mainly (though not exclusively) is not there if weather is dry. What is like source / cause? Also have had ignition light stay on on one occasion at start up for duration of short trip (1.5 miles or so). On switching engine off and restarting after this short trip it reverted to working normally and going out when engine started. Likely cause of apparent temporary malfunction?
Sounds like you may have a concern with the aux belt tensioner, you should have your vehicle checked out