WS6

WS6Oxygen Sensors on Vehicle

Make Toyota Model       Year 1998

Zirconium Operation

Mounted in the exhaust manifold output

The (Zirconium) O2 sensor creates its own voltage. It operating after it has been heated by the engine temperature. Once it reaches this temperature, the ceramic becomes conductive to oxygen ions. As oxygen ions pass through it, the zirconium dioxide generates an electric charge. The greater the difference between the oxygen in the manifold and the amount outside, the more ions pass through the sensor in an attempt to reach equilibrium, and the greater the charge that is developed. The platinum electrodes accumulate this charge and send it through the wires and to the ECU, and the computer can then tell from the strength of the charge if the fuel/air ratio is too lean, or too rich or just right.

This is a perfectly good O2 sensor as a result reacts quickly to sudden changes in driving and quickly responds into closed loop. 

 

 Four Wires

Colour                                        Use or Purpose

Grey                                           Sensor ground

Black                                          O2 Signal

White                                          Power Heater

White                                          O2 Heater

Zirconia switching sensor

 

The signal which I assume is the wave is stay rich to 800mV at 2500rpm then quickly lean to about 200mV to go into closed loop. The graph indicate the signal volts at acceleration position, suddenly drop below idle operation level (lean) is than slowly induce again.

High voltage records        800mV

Low voltage records         200mV

Average voltage records 250mV

 Cross Counts records three

Signal pattern at Idle

High voltage records 800mV (rich)

Low voltage records 200mV (Lean)

Average 400mV (prefect form of O2 sensor)

Cross Counts two

If the signal is not cycling normally, describe what the signal does:

The volts range record the highest of 0.8volts indicate rich mixtures and lowest of 0.20volts indicate lean mixture. While the engine is at idle at operating temperature, this make the pattern go rich and lean rabidly. Each cycling should be in 3 cross counts.

Oxygen Sensor in rich condition

High voltage 0.901v

If this signal is not going high normally, describe what the signal does:

When the engine rev’s up, and the voltage increase to 0.91v the signal rabidly constant at accelerate point, this indicate rich mixture. 

 

6.0 Make this Oxygen Sensor go lean 

The diagram shows Oxygen signal lean voltage test result is -1volt, this create by sudden deceleration cause the voltage lean at -1volt in 0.25seconds.

 With sudden acceleration during engine idle this we try to capture the respond time and how quick the sensor respond due engine throttle position. Show in the red line indicate the voltage induce at the response time of 0.25ms.