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What is the sensor after the catalytic converter?
Oxygen Sensors, commonly referred to as O2 sensors, are part of your vehicles emission system. The purpose of the downstream, after converter, sensors is to monitor the quantities of harmful exhaust gases flowing into and out of the catalytic converter to ensure the converter is working properly.
What O2 sensor is after the catalytic converter?
The oxygen sensor closest to the engine and in front of the catalytic converter, usually termed the upstream sensor, is the more sensitive, and serves to fine tune the air-fuel mixture. The downstream sensor, farthest from the engine and after the catalytic converter, evaluates how well the catalytic converter works.
What does a post catalyst oxygen sensor do?
The signal from the pre-catalyst oxygen sensor is primarily responsible for air-fuel mixture adjustments, while the post-catalyst oxygen sensor signal monitors the performance of the catalytic converter and the amount of oxygen being absorbed during its operation.
Is the after catalyst oxygen sensor used for engine?
Specifically, that it plays no role in engine mixture control. There is generally no disagreement with the role in catalyst testing. The question: are there any engines where this sensor is used by the engine control computer to modify the fuel mixture or other operating parameters?
What does a pre cat sensor on a catalytic converter do?
A switching voltage on the post-cat sensor indicates that the gases are passing across the catalytic converter’s ceramic monolith without being subjected to chemical change and therefore the cat requires replacing with a known good unit, providing that the pre-cat waveform is within specification. A typical Zirconia lambda sensor has four wires.
Can a spacer be added to an O2 sensor?
Adding the spacer introduces a dead-spot where exhaust gas doesn’t flow across the O2 sensor as it would when the O2 sensor is installed in its proper location.
How does the pre and post catalytic converter signal transition?
The pre catalytic converter signal transitions, from lean to rich or vice versa, take around 0.5 s. The post catalytic converter sensor signal Channel B remains around 0.1 V, indicating a lean output from the catalytic converter, irrespective of the rich mixture inputs indicated by the pre catalytic converter sensor Channel A.