Mk3 Gti 8v - Losing Water - Any idea's ??

[Carl MK3 GTI 8V]

if u regularly park in the same place check the ground as coolant will stain it.
It may only leak when the car is on due to the pressure but worth a look wont be your headgasket if this is the case.
my own waterpump was slightly leakin and was fixed by adding radweld!

[AudiA8Quattro]

As previously said, pressure test the system.
I bought a tester on ebay for £90, found my leak on the A8 in a few minutes, and i douby i would of ever found it without the tester.
Its a great tool to have if you work on different cars.

[veedubFanatic]

As previously said, pressure test the system.
I bought a tester on ebay for £90, found my leak on the A8 in a few minutes, and i douby i would of ever found it without the tester.
Its a great tool to have if you work on different cars.

Useful, but as you saying, if you work a lot on cars. it is mainly used for finding blowing on valves or compression rings. there is no point in spending 100 quid on tool that is going to be used once. if it is matter of leaking, first of all its best to check coolant and oil, or you can go to nearest garage and do testing- that should be cheaper. besides if it was head gasket or cylinder wall,  car wouldn't pull as before as there wouldn't be enough compression on one of the cylinders.
Second beside is that I wouldn't like to find out that the compression on one or more cylinders is far lower than it should be and it is not due to the head gasket failure...

[kr1s77]

I bought a new bottle and cap from ecp today £12.75. Gonna fit it in the morning

[AudiA8Quattro]

As previously said, pressure test the system.
I bought a tester on ebay for £90, found my leak on the A8 in a few minutes, and i douby i would of ever found it without the tester.
Its a great tool to have if you work on different cars.

Useful, but as you saying, if you work a lot on cars. it is mainly used for finding blowing on valves or compression rings. there is no point in spending 100 quid on tool that is going to be used once. if it is matter of leaking, first of all its best to check coolant and oil, or you can go to nearest garage and do testing- that should be cheaper. besides if it was head gasket or cylinder wall,  car wouldn't pull as before as there wouldn't be enough compression on one of the cylinders.
Second beside is that I wouldn't like to find out that the compression on one or more cylinders is far lower than it should be and it is not due to the head gasket failure...

Very true.
I would suggest getting a garage to do the test, it should be cheap.
I just like collecting tools 

[veedubFanatic]

I bought a new bottle and cap from ecp today £12.75. Gonna fit it in the morning

let us know after fitting if it changed anything. 

[kr1s77]

will do, fitted it yesterday morning and checked it today. so far ok, i'll report back in a week 

[Alec]

Plastic flange where a hose meets the block is common failure on mk3's and mk2's. I had exactly the same symptoms

Mine went on the passenger side of the block and was only noticeable when engine was up to temp and you could just see a slight bubble and steam

[RBL8vGTI]

Hi there, I wonder if anyone can shed some light on this. I have to fill up my water probably every 2-3 weeks as falls below the min level on my water expansion bottle and temp light flashes on dash, have visually checked rad and pipes and no obvious leaks so why do i have to fill up the water so much, head gasket problem maybe ??  Anyone had any similar issues, any thoughts welcome. Thanks James

i have had a similar problem just a slight water leak .....i found it by doing the following....looking into the engine bay on the 8v engine....on the right side at the end of the cylinder block just above the gearbox bell housing you will see an plastic 90 degree elbow pipe ...it is attached to the end of the block via the moulded plastic flange and an rubber o ring, using two 10mm bolts i think.......heres the trick wait until it is dark....start the engine let it run for a while......then shine a torch into engine bay around.....the 90 degree elbow and what i found was that the leak was just vapourising between the flange and  o ring seal ...and you could only spot the very fine vapour leak by torch at nite..!.......either the 0 ring had failed or the plastic elbow had deformed with the heat over the 12 year period...worth checking all the other coolant hase connection areas with a torch in the dark just in case it mite be venting anywhere else in the engine bay....hope it works for you - good luck