Have a ford mondeo 2.0l auto and water keeps leaking out down the wing and making puddle, have found it is coming from the overflowon hole on the cooling resivoir but the temp gauge is normal but fan starts running louder and more frequent to keep engine cool what could be the cause of this?

marc, June 2009

Possibly-

Faulty filler cap on coolant reservoir.

Coolant mixture too weak - anti freeze not only stops it freezing, it also raises the boiling point

Cylinder head gasket failure.

pdf99, June 2009