Hi all,

My 1993 940 Turbo with 309k seems to be loosing a 1/2" of fluid every few days in the expansion tank. My wife overheated the car a few months ago when the heater hose blew but I replaced the hose, thermostat, radiator, water pump etc.

The car runs fine but I am wondering where this coolant is going becuase I see no leakage at all.
I suspect it is the head gasket but there is no bubbling in the expansion tank when cap is off, no oil in the coolant, no white smoke out the tail pipe, no milky colored oil.

Is there any simple and effective way to check for a failed head gasket ??.
Thank you !