i seem to have to top my water up on a weekly basis just lately

it doesnt appear to be leaking to the road anywhere so where is it going. the oil seems pretty normal, no white sludge or anything,

power seems normal also, it has always seemed to run a tad rich, and get crappy mpg, the heater works and it doesnt overheat or anything, i do get the normal white vapour on start up which can turn to darker colour which indicates the rich running i presume.

 

ive done a seach and rad that pcv and fuel daigphram might help, but it doesnt explain where the waters going.

mine did that and after a few weeks i found out it was the water pump, also check your carpets driver/passenger side heater will work but you could still have a leak there.

Mine does the same.

I tried compression testing, first time; Shit!! dodgy figures.

Second time, done under more constant conditions and the figures were fine.

I get the feeling on mine it is to do with headgasket but it seems ok for the moment.

 

Might want to check simple things like the radiator cap first.