today after work, i started my car and the low water lgiht was flashing away and bleeping, stopped the engine, had a look, Empty, bare in mind i topped it up of saturday! looked for any obvious signs and could see no leeks or any odd residue on the the inside of the oil cap. drove home (half a mile or so) got back and checked again, on the maximum line, now i'm not quite sure what is going on and am very confused!

At first thoughts could have been signs that it could be head gasket failure of sorts, then thought about leeky hose but cant see any of these issues!

would it be worth whiel changing the thermostat or something?

Hope you can and advise me what to do as i really like this car!!

Regards

James.

Remove the engine cover and look for signs of leakage from the coolant housing on the passenger side of the engine just above the gearbox. G12 will leave a pink residue, alternatively it could be a leaking water pump at the other end of the engine.

probably a leaking water pump,

leave the car running and check under the car for water drips

Did you top it up after you found it was empty or did it go back to maximum in the header tank without you doing that? If so then it sounds like an air lock somewhere, or the coolant isn't circulating properly which could either be the thermostat or the water pump failing.

Water pump failure on the TDI-110 tends to cause over-heating, as one of my mates found out the hard way. Fortunately, he was due a cambelt in about 6_000 miles anyway. His mechanic was very impressed with me for correctly diagnosing the problem from some 500 miles away!

But I'd concur that if the car needed topped up there's a leak out one of the ends of the block, or though the pump, and an airlock if it didn't need topped up.

no didnt top up at all, drove home and all was normal!!! odd one! i shall change the thermostat tommorow and see how it goes! should i bleed the whole system to get rid of a possible air lock?

Yep, bleed the whole lot and squeeze the pipes to force any air out to the expansion tank.

You can get G12++ coolant cheap from here http://www.vwspares.co.uk/octaviacooling.php

im lost why are you telling him to bleed the whole lot and change the fluid????

he must have a leak if it suddenly lost water and hasnt had a coolant change recently so the above is pointless

you need to find the leak

your best bet is to buy a pressure tester from sealey £12 and pressure test the system this will hopefully highlight the issue

1 if it holds pressure then its a mystery jobs a goodun just top up and monitor

2. if it loses pressure you have a leak and with it under pressure it should show itself fairly quick

also once the cap is off have a smell make sure it doesnt smell of oil or pertol

dont spend silly money flushing the coolant out when you still dont know what the problem is

HTH

He hasn't lost any coolant, the coolant was back to the maximum level after he got home. That suggests to me there is air in the system. If he loost coolant the coolant would constantly be at the minimum level, not just on one occasion