What should you do if the engine temperature gauge suddenly begins to rise while traveling?

If the engine temperature starts to rise, stop the car, turn off the engine, allow the engine to cool* and then check the coolant level. If you cannot remedy the fault yourself you must take the car to a workshop.

If the engine temperature rises so high that the needle enters the red warning area, and you cannot remedy the fault yourself, the car must be towed to a workshop to avoid engine damage.

* If you do not allow the engine to cool before checking the coolant level you risk burning yourself from scalding water vapor when opening the filling cap.