Just open the drain valve and let out enough coolant so the coolant level in the engine is below the sensor. You do not have to drain the entire radiator. Replacing a coolant sensor requires draining some of the coolant from the cooling system. Abnormally high engine temperatures can damage these components and may cause them to misbehave or fail prematurely. It is also a good idea to replace the coolant sensor and thermostat if the engine has experienced a case of severe overheating.
Installing a new sensor can eliminate a lot of potential problems down the road. Why ? Because coolant sensors can deteriorate with age and may not read as accurately as they did when they were new. But many experts also recommend installing a new coolant sensor if you are replacing or rebuilding an engine. A coolant sensor that is shorted, open or reading out of range obviously can't provide a reliable temperature signal and must be replaced for the engine management system to function properly. Most coolant temperature sensors are not replaced unless they have failed. A quick trip to a qualified mechanic with a diagnostic computer will tell you if the check engine light has anything to do with a coolant temperature sensor or not.Įngine Coolant Temperature Sensors replacement In many vehicles, a faulty coolant temperature system will trigger a check engine light or service engine light on your car's dashboard. This can possibly happen when the coolant is leaking, causing the temperature sensor to behave erratically. If everything else is in order, failure in this test should be because of a faulty coolant temperature sensor.Īnother telltale sign of your coolant temperature sensor not functioning properly is if your engine is overheating frequently. To confirm, you could run your vehicle through an emissions test. If you start having trouble starting your vehicle after it has reached its normal operating temperature, this is usually a very good sign that you need to have the coolant temperature sensor checked. If your vehicle starts to use a lot more gasoline than usual, or black smoke is starting to come from the exhaust pipe, these are indicators that the coolant temperature sensor in your vehicle could be defective, and needs to be replaced. Symptoms of a Bad Coolant Temperature Sensor