Automobiles encompass a number of sensors such as the oxygen sensor,air-fuel ratio sensor, parking sensor and tire push monitor sensor(TPMS). Each sensor is supposed for a specific purpose that helps thevehicle operation at optimal efficiency. The oxygen sensor is one of theimportant sensors the checks the air-fuel ratio and exhaust emissions.This buyer"s guide offers you the simple details, place andfunctionality of the oxygen sensor. Us make it straightforward at to discover the right oxygen sensor replacement for her automobile.

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Function of one Oxygen Sensor

The oxygen (O2) sensor senses the amount of oxygen in the vehicle"s exhaust. The is usually situated in the exhaust pipe. The oxygen sensor reading is offered by the Engine control Unit (ECU) to regulate the quantity of air and fuel sent to the engine. The oxygen sensor greatly serves two purposes: it helps preserve the perfect air-fuel ratio, thereby avoiding the engine from running lean/rich; it likewise reduces the exhaust emissions. One finish of the oxygen sensor detects the quantity of oxygen if the other end connects come the wiring that relays the sensor"s analysis to the ECU.


Heated and also Non-heated Oxygen Sensors

Oxygen sensors need an optimal temperature of 650?? Fahrenheit to role effectively. Non-heated sensors, i beg your pardon were supplied in older automobiles, were heated by the exhaust gases. The disadvantage of these sensors were the it could take a minute or much longer to with the temperature required for operation. Non-heated sensors overcame this trouble through a heater element, a resistor, which heats the sensor come the required temperature for operation.

Narrowband and also Wideband Oxygen Sensors

Narrowband oxygen sensors inform the ECU even if it is the engine is to run lean/rich with recommendation to the stoichoimetric air/fuel proportion (14.7:1). Wideband oxygen sensors, frequently referred to together air-fuel ratio sensors, phone call the ECU just how rich or lean the engine is running in comparison v the stoichoimetric ratio. Wideband oxygen sensors are commonly used in more recent automobiles.

Find a much more detailed explanation ~ above the difference between oxygen sensors and air-fuel proportion sensors in this link: Oxygen or wait Fuel proportion Sensor

Upstream and Downstream Sensors

The upstream oxygen sensor is situated before the catalytic converter conversely, the downstream oxygen sensor is situated after the catalytic converter. The upstream sensor monitors the level that pollutants in the engine"s exhaust and also sends this info to the ECU that repeatedly adjusts the air-fuel ratio. The downstream sensor measures the level the pollutants passing v the catalytic converter. The details from the upstream and also downstream sensors are contrasted by the ECU. If the readings from the 2 sensors become an ext similar to each other, the ECU cause a catalyst inefficiency code.


Knowing the place of the oxygen sensor at error is important. The number and location that the oxygen sensors are specific to every vehicle"s year, make and model. The place of the oxygen sensor is usually figured out by position (sensor 1, sensor 2) and by cylinder bank (bank 1, financial institution 2).

Bank 1 is the next of the engine wherein cylinder #1 is located.

Bank 2 is the contrary to financial institution 1.

Sensor 1 is the upstream sensor.

Sensor 2 is the downstream sensor.

In situation of a four-cylinder engine, over there is just one bank: financial institution 1.

The following connect depicts the various places of oxygen sensors:Location that the Oxygen Sensor and Its bank


An oxygen sensor may gain damaged due to normal wear and tear. However, end time, carbon store may build up end the sensors, preventing them indigenous functioning properly. The sensor can likewise get contaminated with silicon contents from the coolant or anti-freeze.


When the oxygen sensor starts to fail, the exhibits a few symptoms. Few of them are as follows:

Rough Engine Idle

A negative oxygen sensor will send incorrect details to the ECU. This may result in the injection of much more fuel to the engine 보다 required, leading to the engine to stall. This, in turn, root cause the engine to endure a stormy idle.

Increased Emissions

A defective oxygen sensor will fail to store the exhaust emissions under check, thereby resulting in raised exhaust emissions. Raised emissions are as result of the engine to run rich/lean.

Poor Gas Mileage

An automobile"s gas purpose of use is disrupted by a malfunctioning oxygen sensor. The bad sensor will certainly make the ECU deliver an improper lot of fuel come the engine resulting in decreased gas mileage.

Engine Misfiring

When the lot of air-fuel mixture sent out to the engine is not optimal, the combustion in the engine cylinders gain affected, which can reason the engine come misfire. This typically occurs either as soon as the engine accelerates or idles. Engine hesitation, which occurs during acceleration, is additionally an indicator that a negative oxygen sensor.


Having your oxygen sensor on regular basis cleaned because that impurities deserve to ensure their ideal function. Some cars have a distinct O2 sensor irradiate on their dashboard that suggests when to check the oxygen sensor. Unheated sensors normally last 30,000 come 50,000 miles, while newer oxygen sensors must be changed at about 100,000 miles. This details is usually noted in the vehicle"s manual. Learn an ext about oxygen sensor"s life expectancy in this link: Oxygen Sensor Life Expectancy

Direct-Fit or Universal-Fit

Direct-Fit Oxygen Sensor

The surname of this format is pretty self-explanatory. This oxygen sensors room designed to exactly bolt ~ above your applications without any extr modifications.

Universal-Fit Oxygen Sensor

The alternate to a direct-fit layout is the universal-fit oxygen sensor i m sorry does require some boy modifications. This style fits numerous applications but you still have to confirm your application before purchasing. This layout is recommended if your vehicle currently has a universal-fit oxygen sensor in that or if you are looking for a more cost-effective option.

Oxygen Sensor Kit dead a wide selection of oxygen sensor kit for every make and also model. Gaining an oxygen sensor kit will provide you a huge discount. We additionally stock air-fuel ratio sensors and also other sensors.

Finding your Oxygen Sensor"s OEM part Number

If for any type of reason girlfriend cannot find your oxygen sensor by entering her vehicle"s year, make and model, girlfriend can uncover it by its Original equipment Manufacturer (OEM) number. The OEM component number can be found directly on the component itself. Friend can additionally call a dealership through your VIN, and they will carry out you v the OEM component number. Friend can offer one of our auto specialists a contact at 1-888-907-7225 for additional assistance in purchasing your oxygen sensor.

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Frequently request Questions

How countless oxygen sensors walk my car have?

This depends on your automobile"s year, make and also model. Older automobiles had a minimum of 2 sensors whereas more recent automobiles deserve to have six, eight or more oxygen sensors.

What is California emissions sensor?

This sensor is design specially to accomplish the emissions specifications because that the State of California. You can gain California emissions compliant sensors for your auto at

My oxygen sensor has actually an orange/black/white color. What does that mean?

An orange-colored oxygen sensor is commonly an clues of command poisoning. The oxygen sensor might also turn black color indicating carbon buildup or might turn white as result of silicone poisoning or antifreeze contamination. The resource of these problems should be inspected and fixed, prior to replacing the oxygen sensors.

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What execute the P0130 and P0136 codes mean?

The P0130 code indicates the malfunctioning that the oxygen sensor (Bank 1, Sensor 1) and P0136 code suggests defective oxygen sensor (Bank 2, Sensor 1).

Find more FAQ regarding oxygen sensors in this link: just how Much does an Oxygen Sensor Cost?