2003 Saturn ION L4-2.2L VIN FFACTORY OEM SERVICE PROCEDURE

Coolant Temperature Sensor/Switch (For Computer): 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.

Factory service manual diagram



1. Turn OFF the ignition.
2. Drain the coolant system to below the engine coolant temperature (ECT) sensor. Refer to Draining and Filling Cooling System in Cooling System.
3. Disconnect the engine coolant temperature ECT sensor electrical connector.
4. Carefully remove the ECT sensor.

INSTALLATION PROCEDURE

NOTE :
- Replacement components must be the correct part number for the application. Components requiring the use of the thread locking compound, lubricants, corrosion inhibitors, or sealants are identified in the service procedure. Some replacement components may come with these coatings already applied. Do not use these coatings on components unless specified. These coatings can affect the final torque, which may affect the operation of the component. Use the correct torque specification when installing components in order to avoid damage.
- Use care when handling the coolant sensor. Damage to the coolant sensor will affect the operation of the fuel control system.

Factory service manual diagram



1. If you are reinstalling the original sensor, or if you are installing a new sensor without a sealer, coat the threads with sealer Saturn P/N 21485278 or an equivalent.
2. Install the ECT sensor.

NOTE: Refer to Fastener Notice in Service Precautions.

Tighten the ECT sensor to 10 N.m (89 lb in).

3. Connect the ECT sensor electrical connector.
4. Refill the engine coolant system. Refer to Draining and Filling Cooling System in Cooling System.

Factory Service Tools

Use the Manual With the Right Hardware

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When to See a Mechanic

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

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