I get through water in my car realy fast, the car is garaged most of the time and I am always under the bonnet. Every time I check the water (Regularly) it has dissapeared from the header tank and needs a pint or so to top it back up.
There is no visable leek or steam when the car is hot and there is no wet carpets in the car or wet patch under the car.
The water is clean and no sign of gung in the oil or water.
Could I have a porouse head.
The temperature usually sits on 90 when moving but creeps up to 100 in traffic, on my last trip even though it was not hot out and I was moving I noticed the needle had settled just above 90, a bit higher than usual.