Automobiles incorporate a number of sensors such as the oxygen sensor,air-fuel ratio sensor, parking sensor and tire push monitor sensor(TPMS). Every sensor is expected for a specific purpose the helps thevehicle run at optimal efficiency. The oxygen sensor is one of theimportant sensors the checks the air-fuel ratio and exhaust emissions.This buyer"s guide provides you the basic details, location andfunctionality of the oxygen sensor. We make it simple at to find the appropriate oxygen sensor replacement for your automobile.

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Function of one Oxygen Sensor

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


Heated and Non-heated Oxygen Sensors

Oxygen sensors need an optimal temperature of 650?? Fahrenheit to role effectively. Non-heated sensors, i m sorry were offered in older automobiles, to be heated by the exhaust gases. The disadvantage of this sensors were that it can take a minute or longer to reach the temperature required for operation. Non-heated sensors overcame this problem through a heating element, a resistor, i beg your pardon heats the sensor come the forced temperature because that 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 reference to the stoichoimetric air/fuel proportion (14.7:1). Wideband oxygen sensors, generally referred to together air-fuel ratio sensors, call the ECU just how rich or skinny the engine is running in comparison through the stoichoimetric ratio. Wideband oxygen sensors are frequently used in newer automobiles.

Find a more detailed explanation top top the difference between oxygen sensors and air-fuel ratio sensors in this link: Oxygen or air Fuel proportion Sensor

Upstream and also Downstream Sensors

The upstream oxygen sensor is situated prior to the catalytic converter vice versa, 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 details to the ECU that repeatedly adjusts the air-fuel ratio. The downstream sensor procedures the level that pollutants passing through the catalytic converter. The information from the upstream and also downstream sensors are compared by the ECU. If the readings native the two sensors become more similar to every other, the ECU cause a catalyst incompetent code.


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

Bank 1 is the side 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 instance of a four-cylinder engine, over there is only one bank: financial institution 1.

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


An oxygen sensor may get damaged as result of normal wear and tear. However, over time, carbon deposits may construct up over the sensors, avoiding them from functioning properly. The sensor can also get contaminated with silicon content from the coolant or anti-freeze.


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

Rough Engine Idle

A negative oxygen sensor will certainly send incorrect information to the ECU. This may an outcome in the injection of much more fuel to the engine 보다 required, resulting in the engine to stall. This, in turn, induces the engine to endure a turbulent idle.

Increased Emissions

A defective oxygen sensor will fail to keep the exhaust emissions under check, thereby resulting in raised exhaust emissions. Enhanced emissions are because of the engine to run rich/lean.

Poor Gas Mileage

An automobile"s gas usage is disrupted by a malfunctioning oxygen sensor. The poor sensor will certainly make the ECU provide an improper quantity of fuel to the engine result in decreased gas mileage.

Engine Misfiring

When the quantity of air-fuel mixture sent to the engine is no optimal, the combustion in the engine cylinders obtain affected, which can reason the engine come misfire. This generally occurs either as soon as the engine accelerates or idles. Engine hesitation, which occurs during acceleration, is also an indicator the a bad oxygen sensor.


Having her oxygen sensor regularly cleaned because that impurities can ensure their ideal function. Part cars have actually a unique O2 sensor irradiate on your dashboard that suggests when to inspect the oxygen sensor. Unheated sensors typically last 30,000 to 50,000 miles, while more recent oxygen sensors should be replaced 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 nice self-explanatory. This oxygen sensors room designed to specifically bolt ~ above your application without any additional modifications.

Universal-Fit Oxygen Sensor

The different to a direct-fit layout is the universal-fit oxygen sensor i m sorry does call for some minor modifications. This layout fits hundreds of applications but you still need to confirm your application prior to purchasing. This style is encourage if her vehicle already has a universal-fit oxygen sensor in that or if girlfriend are trying to find a much more cost-effective option.

Oxygen Sensor Kit carries a wide variety of oxygen sensor kits for every make and also model. Obtaining an oxygen sensor kit will provide you a big discount. We likewise stock air-fuel proportion sensors and other sensors.

Finding your Oxygen Sensor"s OEM part Number

If for any kind of reason friend cannot find your oxygen sensor by entering your vehicle"s year, make and model, friend can find it by its Original devices Manufacturer (OEM) number. The OEM component number have the right to be found straight on the component itself. Girlfriend can likewise call a dealership through your VIN, and they will carry out you v the OEM component number. Girlfriend can offer one of our vehicle specialists a speak to at 1-888-907-7225 for further assistance in purchasing your oxygen sensor.

Check out"s shipping and also warranty policies.

Frequently request Questions

How numerous oxygen sensors does my automobile have?

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

What is California emissions sensor?

This sensor is design specially to satisfy the emissions specifications because that the State of California. You can get California emissions compliant sensors because that your car at

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

An orange-colored oxygen sensor is usually an indication of lead poisoning. The oxygen sensor might likewise turn black color indicating carbon buildup or may turn white because of silicone poisoning or antifreeze contamination. The resource of these troubles should it is in inspected and also fixed, prior to replacing the oxygen sensors.

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What execute the P0130 and also P0136 password mean?

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

Find more FAQ concerning oxygen sensors in this link: how Much go an Oxygen Sensor Cost?