white sludge in coolant 944 turbo?

[p964]

I have slight white sludge on expansion tank coolant cap?
what could this be a sign of head gasket/other internal damage or tired coolant?
car is not smoking and is still performing well

[hab]

If the car does lots of short runs,its probably just condensation build up.

Though it could be a possible head gasket failure in the early stages.

If your coolant resembles chocolate milkshake i.e oil/water mixing, then get it checked out immediately. I personally would do this sooner rather than laterif this is the case, to avoid any potential damage.

Edited by hab on Wednesday 28th February 00:00

[renn68]

Oil in the coolant tank is more likely to be the gasket on the oil cooler/ filter plate - water in the oil - head gasket. A failing head gasket will likely give rough running on start up. When the engine is shut down, the water gets forced past the head gasket as it is under higher pressure and ends up either in the cylinder or crankcase. If the gasket between the oil cooler/filter plate is going, high pressure oil can be forced past the seal into the coolant. I've experienced both in my turbo S.

[hartech]

And you should also change the o ring seals on the small tube that sticks out of either the block or the housing when you remove the oil filter housing.

Baz