If you feel that your car is running hotter than usual, then there are several steps to take in order to help you understand what's going on.
Green Fluid, Rotten Eggs?
The first thing that you need to do is to park, turn off the engine and look underneath. If you notice a green-coloured fluid beneath, then you need to open the bonnet. If you can detect a whistling sound, then this is evidence of a leaking cooling system. Further evidence of this can be a very strange and unusual smell, which is the coolant as it is being atomised and turned into steam. Some people say this is a little bit like rotten eggs. Since the cooling system is under a great deal of pressure, you should be able to actually see some bubbling when you pinpoint the source of the whistling sound. Next step is a visit to your mechanic.
Fluid in the Overflow?
If you cannot see or hear anything, then you should carefully open the overflow reservoir, but never the radiator. Always use a rag as you carefully turn the top. If there is no fluid inside then you need to report to your mechanic's shop as soon as possible. Always be careful when driving a car that is overheating and if the temperature gauge goes into the red for any considerable period of time then you should have it towed instead. You have to be careful as a minor repair could end up costing a lot of money otherwise.
Could It Be the Cooling Sensor?
Alternatively, if you feel that the car is not running "dangerously" in the hot zone but that the water temperature gauge is higher than normal, then you need to see if the cooling fan is engaging or not. If it doesn't as the car is idling and the water temperature gauge rises then this probably means that you have a bad sensor. This is something that you can get from an auto parts store or get your mechanic to fix fairly readily.
What about the Thermostat?
If, on the other hand, you notice that the fan is working but the temperature is still climbing this could mean a bad thermostat. The thermostat is to be found underneath the hose that leads from the top of the engine back towards the radiator. Once again, this can be fairly readily replaced by your mechanic.
Pointing to the Water Pump or Radiator
If neither of these elements seems to be the problem then you likely have two potential culprits remaining. Firstly, the water pump could be on its way out or the radiator itself could be faulty. This will necessitate a trip to your radiator shop to see if either component can be fixed or will need to be replaced.
For more information, contact a business such as Natrad.