Hello, a few months ago, like the moron I am, I ran my car out of oil. since then its needed more water and im sure its going through a bit more oil, in the last few days its gotten worse, not holding water but no leak, the temp goes sky high and the heaters blow cold air, the thermostat has been changed, worked for 10 mins then stopped, its a fiat punto r reg 1997, should i replace gaskets ie rocket, head or could it be something worse?