I've done every thing in the book i seem to be loseing water everyday but there is none ever on the ground where could it be going also when sitting at a stop light the temp goes up about 240 then drops to normal while driving it runs normal temp then the temp will go up and down it does this with the radiator full i park and check it in the morning i have to add about a gallon every morning what could be the problem can anyone help it is on a cadillac eldrodo i don't know what year its a older model thanks