Engine Coolant Temperature Sensor 2 Circuit Range/Performance

What You Might Notice

• Check Engine Light illumination
• Poor fuel economy
• Black smoke from tailpipe
• Rough idle or stalling
• Engine misfires

Most Common Causes

1. 1

   Bad ECT Sensor #2

   Faulty temperature sensor sending incorrect readings to the engine computer.

2. 2

   Wiring Issues

   Short or open circuit in sensor signal or ground wires causing signal loss.

3. 3

   Poor Connections

   Corroded or loose connectors at the sensor or wiring harness preventing proper signal.

4. 4

   Stuck Thermostat

   Faulty thermostat causing incorrect coolant temperature readings to the sensor.

How to Diagnose It

1. 1

   Check Bad ECT Sensor #2 — Faulty temperature sensor sending incorrect readings to the engine computer.

2. 2

   Check Wiring Issues — Short or open circuit in sensor signal or ground wires causing signal loss.

3. 3

   Check Poor Connections — Corroded or loose connectors at the sensor or wiring harness preventing proper signal.

4. 4

   Check Stuck Thermostat — Faulty thermostat causing incorrect coolant temperature readings to the sensor.

How to Fix It

1. 1

   Replace ECT Sensor #2

   Remove and install new engine coolant temperature sensor in its mounting location.

   Engine Coolant Temperature Sensor #2↗
2. 2

   Inspect and Repair Wiring

   Check sensor circuit wiring for breaks, corrosion, or loose connections and repair as needed.

3. 3

   Clean Connector Terminals

   Remove corrosion from sensor connector pins and apply dielectric grease for better contact.

4. 4

   Replace Thermostat

   Replace faulty thermostat if coolant flow is blocked and causing sensor malfunction.

   Engine Thermostat↗