Overheating

All Nissan Pathfinder owners experiencing overheating problems constant or intermittent should always check the coolant level before considering any other factors, including the replacement of parts such as the thermostat, sending unit, gauge, water pump, etc. While those parts do sometimes fail or malfunction, the problem can only be correctly diagnosed if the vacuum coolant system is first purged of all residual air trapped within the system, and the coolant is at the required full level. Any time the radiator cap, or reservoir cap is removed, or any other opening of the system, all air entering the system must be removed and the coolant topped off to ensure that the engine temperature will be within the normal range. While the methods used to do this may vary, it is best to check and recheck when the engine is cold until the coolant level holds halfway between the min and max level on the reservoir tank.