O2 Sensor Replacement Cost

The O2 sensor (also known as the oxygen sensor) is one of the key components in helping your car run efficiently. A faulty sensor can cause poor fuel consumption and can potentially cause serious damage to the engine, so the O2 sensor replacement cost can be far less than the additional fuel or the cost of major engine repairs.

The repair itself is reasonably straightforward, so many people opt to just purchase the part and perform the work themselves. Labor costs at a garage are fairly reasonable too, as it won’t take a trained mechanic long to switch out the parts. It’s usually a quick diagnosis using the engine computer before simply replacing the oxygen sensor with a new one.

If you decide to do the repairs, the cost to replace the oxygen sensor yourself can be between $20-$94, depending on the brand and type of sensor you buy. To have the repairs done by a mechanic the price can be anywhere between $113 to $478 for parts and labor. The big difference in price is caused by the different prices of the sensor for certain models of car, and potentially 2 sensors needing replaced at once.

Replacement O2 Sensor Cost Comparison

There are two ways of replacing your oxygen sensor – do it yourself or have it done at a garage. If you choose to do it yourself the cost will only be for the part (and possibly for an O2 sensor socket), while at a garage you’ll be paying for labor and parts.

We’ve compiled the average costs for parts and labor from a few of the major chains in the country, as well as the expected cost to order the part itself online.

Your Mechanic

Midas

Mr. Tire

NAPA

Pep Boys

Walmart

Amazon

What Is The Oxygen Sensor?

Since 1980, the vast majority of cars have been fitted with an oxygen sensor. It works as part of the emissions controls, and communicates with the engine management computer to help the car run as efficiently as possible while producing lower levels of emissions.

In a gasoline engine there is a particular ratio of gasoline and air that is perfect for combustion. If there’s less air than the perfect ratio requires, there will be additional fuel left over after combustion. This is known as rich mixture. A rich mixture is problematic as it causes excess pollution and can negatively impact the atmosphere.

If the inverse is the case, and there’s more oxygen in the mixture than is necessary, this creates a lean mixture. A lean mixture can result in poor engine performance and may even cause long term damage, alongside producing more nitrogen-oxide pollutants than the perfect mixture.

The oxygen sensor was developed to help combat this issue and prevent excess pollution or damage to the engine. It’s typically placed in the exhaust pipe and it works to detect lean and rich mixtures, and works with the engine’s computer to help adjust the amount of fuel entering the engine. The result is less pollution, better performance and less money spent which is what we strive for at Auto Service Costs.

Benefits of O2 Sensor Repair

Having a working and accurate O2 sensor is essential for achieving optimal performance and fuel efficiency in your car. There are a number of variables which can affect the amount of oxygen available to the engine, such as air temperature, altitude, engine temperature, engine load, barometric pressure and more.

• If you have a faulty oxygen sensor the engine computer is forced to guess the optimal air to fuel ratio, resulting in a loss of performance and potentially damage to the engine.
• The cost of O2 sensor repair is far less than the additional fuel costs (and substantially less than major engine repair) so it’s worth getting it fixed as soon as you can.
• By fixing the sensor you’ll ensure that the car is burning fuel efficiently, and you’re substantially reducing the likelihood of any long term damage to your car.
• A common failure of vehicle inspections in many states all fall back to the oxygen sensor which will require being fixed before returning to the DMV.

When Should You Have The O2 Sensor Repaired?

There are several symptoms to look out if you suspect an issue with the oxygen sensor on your car. The first and most obvious sign will be that the ‘check engine’ light will come on, and your mechanic should be able to confirm that it’s emitting an O2 sensor code. If the garage confirms that the sensor is damaged it will need to be replaced.

There are more subtle signs to be aware of, too. You may find that your fuel consumption increases, the car doesn’t idle as well as it should, it may have problems starting, and it may feel jerky despite a steady throttle. While these symptoms are not always caused by a faulty sensor, it can be the cause of some of them.

How To Replace An O2 Sensor

When you take your car to the mechanic they’ll usually run a few diagnostic tests to confirm the issue. They’ll use an OBD2 diganostic tool to confirm that the check engine light is sending out the code for the oxygen sensor. This process is commonly done during an automotive tune up and shouldn’t cost any extra money to test for. If a car has more than one O2 sensor then the scan should indicate which one is causing the issue.

Once the problematic sensor has been identified by the engine computer, the mechanic will use an oxygen sensor socket to loosen and remove the device. The socket will fit on to a cheater bar and can be purchased from most major car part outlets, so if you’re planning on making the repair yourself it’s a good idea to pick one up. The sensors tend to be fitted fairly tight, so it’s a good idea to use the right socket to prevent damaging the exhaust pipe.

The electrical connection will need to be unplugged to allow the socket to be attached to the device. The socket should need one or two turns to loosen it off, after which it should be easy enough to remove with your hands. You can then begin to screw the replacement sensor in by hand, before tightening it up again with the O2 sensor socket. The electrical connection should then be snapped back on once the sensor is in place. Start the engine back up, and the check engine light should now be off!

Most mechanics will recommend replacing the oxygen sensor with the exact same type that was on the car originally. While an aftermarket O2 sensor may be cheaper, it sometimes won’t work properly with the car’s computer and the engine light will remain on. Occasionally the official O2 sensor costs a little more than the aftermarket part, but you have that extra layer of security knowing it will definitely work properly.

The video below helps explain the whole process.

How to save money on O2 Sensor Repair

When you take your car to a mechanic, you’ll be paying for the parts as well as the labor involved. Garages will often add a mark up to the parts, while the labor costs can often be quite expensive. Replacing the sensor is a job that most people should be capable of handling themselves, provided there’s not a serious issue with the sensor. Occasionally it can rot into the pipe or the catalytic converter, in which case it should be dealt with by a professional to avoid breaking any other parts.

The tricky part of fixing it yourself is actually the initial diagnosis. Most people won’t have access to the OBD2 diagnostic tool that most garages use, however there are a number of smartphone apps that can turn your phone into an OBD2 scanner. If you can confirm that the part has failed and needs to be replaced, you can order it online from a number of major retailers. As mentioned previously, it’s not ideal to pick up low quality aftermarket parts, so find the right bit of equipment and shop around for the best price. You’ll also need an O2 sensor socket, which can be picked up at the same time as your sensor.

When the part arrives you can follow the process outlined above, ideally in tandem with using the manual which came with your car. Most cars will have the sensor in slightly different places, so you can save yourself a lot of time and effort by using the manual. The oxygen sensor is one of the easiest parts on a car to replace by yourself, so you can save money on O2 sensor repair costs by ordering the parts and doing the work yourself. If you struggle to make the repair then by all means take it to a mechanic, but it’s worth trying to do it yourself if money is a concern.

Sample Oxygen Sensor Replacement Costs

Below is a table of sample repair costs for the best selling cars in the USA this year. The prices are indicative of the typical costs you can expect when taking the car to a mechanic, however they may vary from state to state.