there's a coolant pipe that runs in the valley of the engine, it can have a slow leak. The leaked coolant runs down behind the engine. It's a hard one to trace.
You're loosing a litre a month? Have you replaced the coolant, and what colour is it, the orangey/pink stuff leaves a dried tell tale if leaking. Also another area is the thermostat tower and water pump, check these places after a run when the coolant is up to temp.
You're loosing a litre a month? Have you replaced the coolant, and what colour is it, the orangey/pink stuff leaves a dried tell tale if leaking. Also another area is the thermostat tower and water pump, check these places after a run when the coolant is up to temp.