Q: My Nissan Frontier truck is overheating. The smog technician said it needs a new thermostat. Would you like to take a look, give m

Hello, thank you for writing in. If the overheating is only happening when you are at a stop, then you want to focus on the water pump and the cooling fans first. While the thermostat can cause overheating when it fails, its function is dependent on temperature, not engine RPM. The cooling fans however are meant to turn on and assist with cooling once the engine hits a certain temperature. If they are not turning on, when the vehicle sits idle, there is no airflow over the radiator to help cool off the hot coolant. Also at idle with lower RPMs, the water pump is not pumping as fast, and the flow of coolant is slower through the engine. If it is starting to fail, the colder coolant may not be getting pumped into the engine fast enough. Only further testing will tell, and the thermostat can also be tested if desired. For more help, contact our service department.