Hi, earlier on today i noticed that my engine was running a little too hot, so i re-filled the engine coolant with de-ionised water. When i was driving i noticed that my exhaust was ratling when i accelerated and changing into 2nd gear was also a bit rattly and problematic. I managed to make it home with the car and i noticed that there was a trail of water (i think, 90% sure) running behind the car. I was just wonder if this has caused any kind of permanent damage. What should i fill the engine coolant with as im now sure its not just water? Many thanks

you should fill the cooling system with 50% water and 50% antifreeze. more importantly, where is your coolant going?! if its on the floor thats usually a better place than disappearing. you need to look for a leak and fix it asap. driving with the engine overheating can cause serious damage (head gasket failure, warped head). if it looks as though you're leaking from the exhaust or cat it probably means the head gasket has gone. fingers crossed that wont happen and you just have a coolant hose with a dodgy jubilee clip or a slight leak on the radiator, both easily and cheaply fixed.

Hmm...ive been using water for past 4 months, as opposed to antifreeze/water combo - what could this result in?? :-|

Also, i topped mine up to max 3 days ago...and needed to again this morning, as it was slightly above minimum - shouldn't have to do it this often, should i?

Sorry to hijack btw - but its the same subject!

if you use water you'll suffer head gasket failure every winter guaranteed, the water freezes so the water pump cant pump ice and it fails quickly, then the ice and broken pump prevents coolant circulation so the engien overheats and warps before the ice even melts. also the coolant system will rust away and block pretty quickly even in summer as the antifreeze contains corrosion inhibitors. basically a lack of antifreeze is very very bad. only a fool would do it.