Strange Overheating???

[Titus A Duxass]

I had something very similar with mine, it looked like it was losing water. The level in the first tank would drop and the red LED would flash.

I changed everything that you have changed, it turn out to be a cracked head. The combustion gases were pressurising the cooling system and forcing the level down. At first this would only happen if I was stuck in traffic or lugging up a long climb (Brenner Pass, etc.). It gradually got worse and started happen after a short drive.

The funny thing was that the temperature gauge hardly moved from normal. This was due the sensor being out of the cooling water, caused by the gases forcing the level down.

It did this for about 2500km before I had a to replace the head.

Get a comp test done, but make sure the engine is up to full working temp first.

If you have a sound bottom end look at changing the head, if not go for a recon motor.

[Jamie25]

Well i did a compression test today and I got the following values....
10.5 bar, 10.25 bar (and a slightly oily plug), 9.5 bar and 8.5 bar.

I've also noticed that the cooling system seems to be keeping some pressure, even when left overnight. I think this indicates the system being pressurised by a leaky head but I'm not sure.

Is the 8.5 bar reading low - should I be worried - does this mean a leaking head/gasket????