Kia Cee'd: Engine Control System / Heated Oxygen Sensor (HO2S) Description and operation

Heated Oxygen Sensor (HO2S) consists of zirconium and alumina and is installed both upstream and downstream of the Manifold Catalytic Converter. The sensor output voltage varies in accordance with the air/fuel ratio.

The sensor must be hot in order to operate normally. To keep it hot, the sensor has a heater which is controlled by the ECM via a duty cycle signal. When the exhaust gas temperature is lower than the specified value, the heater warms the sensor tip.

Knock Sensor (KS) Repair procedures

Removal 1. Turn the ignition switch OFF and disconnect the battery negative (-) cable. 2. Remove the intake manifold. (Re ...

Heated Oxygen Sensor (HO2S) Specifications

Specification HO2S [Bank 1/Sensor 1]   Item Specification Heater Resistance (Ω) 2.4 ~ 4.0 [20°C(68°F)] ...

Other information:

: Starting and Stopping the Engine – Troubleshooting
Starting and Stopping the Engine – Warning Lamps Malfunction Indicator Lamp If it illuminates when the engine is running, the on-board diagnostics system is detecting a malfunction of the vehicle emission control system. If it flashes, engine misfire could be occurring. Increased exhaust ga ...

Kia Cee'd JD Service Manual: Valve clearance adjustment
Valve Clearance Inspection And Adjustment    Inspect and adjust the valve clearance when the engine is cold (Engine coolant temperature : 20°C) and cylinder head is installed on the cylinder block. ...