2006 Chevrolet Optra (CANADA) L4-2.0LFACTORY OEM SERVICE PROCEDURE

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




Engine Coolant Temperature (ECT) Sensor Replacement

Removal Procedure

Factory service manual diagram



1. Relieve the coolant system pressure.

Caution: Refer to Battery Disconnect Caution Battery Disconnect Caution in Cautions and Notices.

2. Disconnect the negative battery cable.

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

3. Disconnect the engine coolant temperature (ECT) sensor connector.
4. Remove the ECT sensor from the electronic ignition (EI) system ignition coil adapter.

Installation Procedure

Factory service manual diagram



1. Coat the threads of the ECT sensor with sealer.

Notice: Refer to Fastener Notice Fastener Notice in Cautions and Notices.

2. Install the ECT sensor into the EI system ignition coil adapter.

Tighten the engine coolant temperature sensor to 20 Nm (15 lb ft).

3. Connect the ECT sensor connector.
4. Fill the coolant system.
5. Connect the negative battery cable.

Factory Service Tools

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

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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.