Coolant Temperature Sensor/Switch (For Computer): Service and Repair

2005 Chevrolet Blazer 4WD V6-4.3L VIN XSECTION Service and Repair


ENGINE COOLANT TEMPERATURE (ECT) SENSOR REPLACEMENT

REMOVAL PROCEDURE

NOTE: Use care when handling the coolant sensor. Damage to the coolant sensor will affect the operation of the fuel control system.




1. Turn OFF the ignition.
2. Loosen the wing nuts on the air cleaner cover and air cleaner outlet duct.
3. Move the air intake assembly aside.




4. Drain the cooling system below the level of the engine coolant temperature (ECT) sensor. Refer to Draining and Filling Cooling System in Cooling System.




5. Disconnect the ECT sensor harness connector.
6. Remove the ECT sensor.

INSTALLATION PROCEDURE

NOTE:
- Refer to Component Fastener Tightening Notice in Service Precautions.
- Use care when handling the coolant sensor. Damage to the coolant sensor will affect the operation of the fuel control system.




1. Coat the threads (only) with GM P/N 12346004 sealer or equivalent.




2. Install the ECT sensor in the engine.

Tighten the sensor to 20 N.m (15 lb ft).

3. Connect the ECT sensor harness connector.




4. Refill the cooling system. Refer to Draining and Filling Cooling System in Cooling System.
5. Install the air cleaner outlet duct assembly and tighten the wing nuts.
6. Connect the negative battery cable.
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.