The coolant temp sensor on a 2007 Chevy Silverado connects to the driver's-side engine head directly in front of the exhaust manifold. The temperature sensor reads the temperature inside the engine head and then relays the reading the ECU (Electronic Control Unit). If the engine temperature reads too high, the "check engine" light turns on to indicate engine overheating. Like all other sensors, over time, it could stop reading the engine temperature correctly and start displaying the check engine light when it shouldn't.
Locate the temperature sensor on the driver's-side engine head. Use the replacement sensor as a visual aid.
Disconnect the wiring harness by pushing on the locking tab in the center of the harness and then by pulling up on the harness to separate it from the sensor.
Remove the sensor from the engine head with an adjustable wrench. The sensor threads into the head; remove it by turning it counterclockwise.
Thread the new sensor into the engine head with your fingers and then tighten it a quarter-turn with the wrench.
Slide the connector of the wiring harness onto the end of the sensor and push down on the locking tab.
