Slight condensation and greasy internal windscreen makes me think I 've a slight cooling leak in the heater matrix or associated hoses around the dashboard. Water level in header is OK but then a little makes a lot of steam! Is the matrix a) expensive and b) a bitch to get at and chaneout? "Bars Leaks" has not helped in this case! Secondly what's the service interval for the timing belt and is it straingtorward?