So, every car made after 1996, has oxygen sensors (O2), before and after, of each catalytic converter.

Most cars, have two (O2) sensors. However, there can be as many as 4, (O2) sensors, depending on your engine and exhaust.

Actually, (O2) sensors, don’t even work, until they have heated up, to over 600 degrees. Therefore, when you start a cold engine, the (O2) sensor is not even working.

Instead, it uses a fixed rich fuel mixture, until it gets a signal, from the heated up oxygen sensor (O2).

And, that why many newer oxygen sensors (O2), contain heating elements. Because, this helps to get them to operating temperature faster. As a result, this lowers the amount of time, your car spends running inefficiently.

The amount oxygen in an engine, is the result of a number of factors including:

  • Air temperature.
  • Altitude.
  • Engine temperature.
  • Load on the engine.
  • Barometric pressure.

The ideal ratio for oxygen and fuel, is 14.7:1, which slightly varies, depending on different types of fuel. In the instance that there is less oxygen present, some fuel will remain, after combustion. Consequently, this is referred to as, a rich mixture. And, is detected by your oxygen sensors (O2).

Both, rich and lean mixtures, are bad for your car, as well as for the environment. A rich mixture results in, a fuel that is not burned. However, a lean mixture, generates nitrogen-oxide pollutants. As a result, leading to, decreased vehicle performance and engine damage.

Firstly, an (O2) sensor, creates a voltage, due to a chemical reaction. As a result, of an off-balanced, fuel to oxygen ratio. So, most car engines can determine, how much fuel to expel into the engine. As a result, of the voltage of the (O2) sensor.

Consequently, if your oxygen sensor fails to function properly, your engine management computer, cannot determine the air fuel ratio. As a result, the engine is forced, to guess how much fuel to use. Therefore, resulting in a polluted engine and a, poorly running vehicle.

Symptoms of a Bad (O2) Sensor

So, when an (02) sensor fails, there are a variety of diagnostic trouble codes (DTCs) that can pop up. Most of the time, a faulty (O2) sensor will result in, a check engine light. And, can also include a fault code, that you can read with an OBD-2 scanner. Based on this fault code, it will point to how it failed. Then, you can move forward with the diagnosis.

Choose Your Help Topic Below

(O2) Oxygen Sensor – Function – Failure Symptoms – With Testing

(O2) Oxygen Sensor – Function – Failure Symptoms – With Testing

Oxygen Sensor (O2) – What Else Could Cause Rich Or Lean Codes

(O2) Oxygen Sensors – Function, Failure Symptoms, Testing Procedures

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