I have 2002 fabia sdi and the temp guage has stated sitting just over half all of a sudden. The top hose of the radiator is hot and the bottom is cold, would this indicate anything? Also there is no coolant leak. The air vents are all fine and blows hot and cold when required.

Quick update the temperature guage started sitting at the usual half way. Later on its now deciding to hardly move at all. Any help would be appreciated.