Automobiles incorporate a variety of sensors such as the oxygen sensor,air-fuel proportion sensor, parking sensor and also tire pressure monitor sensor(TPMS). Each sensor is meant 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 also exhaust emissions.This buyer"s guide offers you the straightforward details, location andfunctionality the the oxygen sensor. We make it easy at to uncover the right oxygen sensor replacement for your automobile.

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Function of one Oxygen Sensor

The oxygen (O2) sensor senses the quantity of oxygen in the vehicle"s exhaust. That is usually located in the exhaust pipe. The oxygen sensor reading is provided by the Engine control Unit (ECU) to control the lot of air and also fuel sent out to the engine. The oxygen sensor largely serves 2 purposes: it helps preserve the perfect air-fuel ratio, thereby staying clear of the engine from running lean/rich; it additionally reduces the exhaust emissions. One end of the oxygen sensor detects the quantity of oxygen while the other end connects to the wiring that relays the sensor"s analysis to the ECU.


Heated and Non-heated Oxygen Sensors

Oxygen sensors require an optimal temperature the 650?? Fahrenheit to duty effectively. Non-heated sensors, i m sorry were provided in enlarge automobiles, to be heated through the exhaust gases. The disadvantage of these sensors were that it might take a minute or much longer to with the temperature required for operation. Non-heated sensors overcame this problem through a heating element, a resistor, i beg your pardon heats the sensor to the required temperature because that operation.

Narrowband and Wideband Oxygen Sensors

Narrowband oxygen sensors educate the ECU even if it is the engine is to run lean/rich with referral to the stoichoimetric air/fuel ratio (14.7:1). Wideband oxygen sensors, typically referred to as air-fuel proportion sensors, tell the ECU exactly how rich or skinny the engine is to run in comparison with the stoichoimetric ratio. Wideband oxygen sensors are frequently used in more recent automobiles.

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

Upstream and also Downstream Sensors

The upstream oxygen sensor is situated prior to the catalytic converter whereas the downstream oxygen sensor is located after the catalytic converter. The upstream sensor monitors the level that pollutants in the engine"s exhaust and sends this info to the ECU that continuously adjusts the air-fuel ratio. The downstream sensor actions the level of pollutants passing with the catalytic converter. The information from the upstream and also downstream sensors are contrasted by the ECU. If the readings indigenous the two sensors become more similar to each other, the ECU root cause a catalyst incompetent code.


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

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

Bank 2 is opposite to bank 1.

Sensor 1 is the upstream sensor.

Sensor 2 is the downstream sensor.

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

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


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


When the oxygen sensor starts to fail, it exhibits a few symptoms. Several of them room as follows:

Rough Engine Idle

A negative oxygen sensor will send incorrect info to the ECU. This may an outcome in the injection of much more fuel to the engine 보다 required, resulting in the engine come stall. This, in turn, root cause the engine to experience a unstable idle.

Increased Emissions

A defective oxygen sensor will certainly fail to save the exhaust emissions under check, in order to resulting in enhanced exhaust emissions. Raised emissions are because 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 poor sensor will certainly make the ECU supply an improper quantity of fuel to 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 burning in the engine cylinders get affected, i m sorry can reason the engine to misfire. This commonly occurs either once the engine speeds up or idles. Engine hesitation, i beg your pardon occurs throughout acceleration, is also an indicator that a negative oxygen sensor.


Having her oxygen sensor on regular basis cleaned because that impurities can ensure their ideal function. Part cars have a unique O2 sensor light on your dashboard that indicates when to check the oxygen sensor. Unheated sensors usually last 30,000 come 50,000 miles, while newer oxygen sensors should be changed at about 100,000 miles. This info is usually provided in the vehicle"s manual. Learn an ext about oxygen sensor"s life span in this link: Oxygen Sensor Life Expectancy

Direct-Fit or Universal-Fit

Direct-Fit Oxygen Sensor

The surname of this format is quite self-explanatory. These oxygen sensors are designed to specifically bolt ~ above your application without any added modifications.

Universal-Fit Oxygen Sensor

The different to a direct-fit style is the universal-fit oxygen sensor i m sorry does need some boy modifications. This format fits numerous applications yet you still have to confirm your application before purchasing. This layout is encourage if your vehicle already has a universal-fit oxygen sensor in the or if girlfriend are looking for a much more cost-effective option.

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

Finding her Oxygen Sensor"s OEM component Number

If for any reason girlfriend cannot uncover your oxygen sensor through entering her vehicle"s year, make and also model, friend can uncover it by its Original tools Manufacturer (OEM) number. The OEM part number have the right to be found directly on the component itself. Friend can likewise call a dealership through your VIN, and they will administer you with the OEM component number. You can offer one of our auto specialists a contact at 1-888-907-7225 for additional assistance in purchasing your oxygen sensor.

Check the end"s shipping and also warranty policies.

Frequently request Questions

How numerous oxygen sensors does my car have?

This relies on her automobile"s year, make and also model. Older automobiles had a minimum of two sensors whereas more recent automobiles have the right to have six, eight or more oxygen sensors.

What is California emissions sensor?

This sensor is design specially to fulfill the emissions specifications because that the State of California. Girlfriend can acquire California emissions compliant sensors because that your automobile at

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

An orange-colored oxygen sensor is typically an indication of command poisoning. The oxygen sensor might also turn black color indicating carbon buildup or might turn white because of silicone poisoning or antifreeze contamination. The source of these troubles should be inspected and fixed, before replacing the oxygen sensors.

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What perform the P0130 and P0136 codes mean?

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

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