{"id":8831,"date":"2021-10-14T19:06:37","date_gmt":"2021-10-14T22:06:37","guid":{"rendered":"http:\/\/107.161.183.10\/~mte\/en\/?post_type=produtosmte&p=8831"},"modified":"2023-05-29T18:57:39","modified_gmt":"2023-05-29T21:57:39","slug":"oxygen-sensor","status":"publish","type":"produtosmte","link":"https:\/\/mte-thomson.com\/en\/produtosmte\/oxygen-sensor\/","title":{"rendered":"Oxygen Sensor"},"content":{"rendered":"

What is an Oxygen Sensor or Lambda Probe?<\/b><\/h3>\n

The Oxygen Sensor, also known as Lambda Probe, is located in the vehicle exhaust, and its main function is to analyze the amount of oxygen present in the gases released by the engine.<\/span><\/p>\n

What is the Oxygen Sensor or Lambda Probe for?<\/b><\/h3>\n

This sensor is for collecting fuel burn information and sending it to the ECM, or engine control module.<\/span><\/p>\n

\"\"<\/p>\n

 <\/p>\n

 <\/p>\n

 <\/p>\n

 <\/p>\n

 <\/p>\n

 <\/p>\n

 <\/p>\n

 <\/p>\n

Internal combustion engines (Otto Cycle, Diesel, or CNG) can only function if there is oxygen, fuel, and heat (combustion or burning is an exothermic reaction, that is, it occurs from the inside out). Without these elements, it is not possible to obtain the internal explosion necessary for the engine operation.<\/span><\/p>\n

The big challenge, however, is getting the balance between fuel and oxidizer \u2013 in this case, oxygen \u2013, which results in the stoichiometric mixture. That is where the oxygen sensor comes in, measuring the unburned oxygen resulted from the engine combustion. If the mixture is lean (more oxygen than fuel) or rich (less oxygen than fuel), the sensor sends an electric signal (in millivolts) to the electronic injection management unit (ECMCU)\u2013 which, based on the information from the sensor, will regulate the fuel mixture, injecting more or less fuel into the combustion chamber. This allows for better engine performance, fuel saving, and lower emissions.<\/span><\/p>\n

 <\/p>\n

\"\"<\/p>\n

 <\/p>\n

 <\/p>\n

 <\/p>\n

 <\/p>\n

 <\/p>\n

 <\/p>\n

 <\/p>\n

Example: For pure gasoline to burn completely, we need 14.7 parts of air for 1 part of fuel. This ratio must be changed according to different conditions, whether environmental (temperature, pressure, humidity, etc.) or related to the vehicle\u2019s own operation (RPM, engine temperature, desired power variation, among others).<\/span><\/p>\n

 <\/p>\n

Oxygen Sensor or Lambda Probe?<\/b><\/h3>\n

The correct and comprehensive name for all types of this product is OXYGEN SENSOR. It accurately measures the oxygen (O<\/span>2<\/span>) present in combustion, regardless of which fuel is used.<\/span><\/p>\n

When the mixture is rich (too much fuel), the voltage generated by the sensor is high (900 millivolts). At this moment, the ECM stops injecting fuel and the mixture becomes lean (too much oxygen). Then the sensor informs the ECU with a low voltage (50 millivolts) and, at this moment, the ECU injects more fuel in the mixture. \u00a0<\/span><\/p>\n

See, on the graph below, the reason why the Greek letter lambda (\u03bb) was adopted to name the sensor.<\/span><\/p>\n

Switching \u2013 Oxygen Sensor \/ Lambda Probe<\/span><\/p>\n

 <\/p>\n

\"\"<\/p>\n

 <\/p>\n

 <\/p>\n

What Is the Lambda Factor?<\/b><\/h3>\n

The letter is also used to define the lambda factor (\u03bb), which corresponds to the equivalence between the actual air-fuel ratio (happening in the vehicle at that time) and the ideal or stoichiometric ratio for a mixture.<\/span><\/p>\n

\u00a0<\/span><\/p>\n

Lambda factor (\u03bb) = <\/span> actual air-fuel ratio<\/span><\/p>\n

ideal air-fuel ratio<\/span><\/p>\n

<alinhar os itens acima como se v\u00ea na refer\u00eancia a seguir (tirada do texto em portugu\u00eas):<\/span> ><\/span><\/p>\n

<\/h3>\n

Ideal air-fuel ratio<\/b><\/p>\n

    \n
  • Gasoline: 14.7: 1 (14.7 parts air to 1 part gasoline)<\/span><\/li>\n
  • Ethanol: 9.0:1 (9.0 parts air to 1 part ethanol)<\/span><\/li>\n
  • Diesel: 15.2:1 (15.2 parts air to 1 part diesel)<\/span><\/li>\n<\/ul>\n

    Thus, we can conclude that when a mixture has more air than specified in the list above, \u03bb > 1 \u2013 that is, the mixture is lean. When the amount of air is below the specified, \u03bb < 1 \u2013 that is, the mixture is rich.<\/span><\/p>\n

    \"\"<\/p>\n

     <\/p>\n

    How Does\u00a0the Oxygen\u00a0Sensor Work?<\/b><\/h3>\n