An oxygen or O2 sensor keeps an eye on the air-fuel mix in your engine to boost fuel efficiency and minimize those nasty emissions.
When it goes bad, your engine’s performance will take a nosedive, potentially damaging parts like the catalytic converter. At that point, replacement becomes the only option.
Wondering how much does an O2 sensor replacement cost?
Let’s break down the expenses and find out how you can identify a failing oxygen sensor before it leads to bigger issues. We’ll also cover the risks of driving with a malfunctioning oxygen sensor and how long they usually last.
This Article Contains:
- How Much Does an O2 Sensor Replacement Cost?
- Can You Drive with Damaged Oxygen Sensors?
- 5 Signs You Need an O2 Sensor Replacement
- How Often Should You Replace Oxygen Sensors?
- What Does an Oxygen Sensor Do?
- Can You Replace Oxygen Sensors Yourself?
How Much Does an O2 Sensor Replacement Cost?
Here’s what you may have to pay for replacing a faulty oxygen sensor:
A. Range
The cost of an oxygen sensor replacement usually falls between $360 and $520.
This includes:
- Cost of replacement parts: $300 to $350 for a pair
- Labor charges: $60 to $170
Note: Manufacturers recommend replacing O2 sensors in pairs (either both upstream or both downstream). That’s because the vehicle’s computer (ECU) may detect inconsistencies between new and old sensors and trigger error codes.
B. Factors Affecting Average Cost
The price for oxygen sensor replacement depends on the local labor costs and your vehicle’s make and model. For instance, luxury or high-performance cars often have more expensive sensors designed for advanced systems.
Other factors influencing the final bill at the car repair shop include:
- Quality of replacement parts: An Original Equipment Manufacturer (OEM) part will cost more than an aftermarket alternative, as it offers better durability and compatibility with your vehicle’s systems.
- Number of sensors: Cars with a single exhaust pipe typically have two sensors, while cars with dual exhaust pipes have four, which can increase repair costs.
- Type of sensor: Zirconia oxygen sensors are the most common type and generally cost less than titania and wideband oxygen sensors. Wideband sensors, found in newer vehicles, are more advanced and tend to cost the most.
- Warranty period: If your car is covered under a manufacturer or factory warranty, oxygen sensor repairs are typically covered at no cost. However, most factory warranties expire after three years or 36,000 miles. So, if the O2 sensors fail after the warranty period, you’ll have to pay the repair costs.
- Other related repairs: Besides billing you for the oxygen sensor replacement service, your auto mechanic will charge extra to repair other damaged parts. These may include the exhaust manifold, catalytic converter, muffler, and more.
Can You Drive with Damaged Oxygen Sensors?
Short answer — no, you shouldn’t.
Ignoring a bad O2 sensor can lead to reduced fuel efficiency, catalytic converter damage, and increased emissions. Additionally, if your state requires annual emissions inspections, your car won’t pass the test due to excess exhaust emissions.
That’s why it’s important to address oxygen sensor issues properly and avoid further complications.
5 Signs You Need an O2 Sensor Replacement
Some indicators of a malfunctioning oxygen sensor include:
- Illuminated check engine light: The ECU (Engine Control Unit) monitors the functioning of oxygen sensors and their heater circuits. If the ECU detects a problem with your car’s oxygen sensors, it’ll turn on the check engine light on the dashboard.
- Poor engine performance: A faulty O2 sensor causes the ECU to miscalculate the air-fuel mixture, which leads to an incorrect amount of fuel being injected into the engine. This can result in engine misfiring, rough idling, and stalling.
- Black smoke: When oxygen sensors fail, the engine can burn too much fuel, resulting in incomplete combustion. This unburnt fuel exits through the exhaust pipe as thick, black smoke.
- Reduced fuel economy: A bad O2 sensor can also increase fuel consumption, affecting your miles per gallon.
- Smell of rotten eggs: The unburnt fuel entering the exhaust can overwhelm the catalytic converter. As a result, the converter may emit hydrogen sulfide, producing a rotten egg smell.
How Often Should You Replace Oxygen Sensors?
Oxygen sensors in older cars last around 40,000 to 70,000 miles, while modern cars can go for roughly 100,000 miles.
However, oxygen sensors can fail earlier due to:
- Increased wear and high mileage
- Damage from substances like oil ash or coolant, which deteriorates their ability to measure the air-fuel mixture accurately
- Use of low-quality or contaminated fuel that affects the combustion process
- Environmental factors such as water and road salt
What Does an Oxygen Sensor Do?
An oxygen sensor monitors the amount of oxygen in the exhaust to ensure the engine runs efficiently and with minimal emissions.
If the mixture is too rich (contains too much fuel) or too lean (contains too little fuel), the sensor sends a signal to the car’s computer to adjust the air-fuel ratio for optimal performance.
Modern vehicles usually have two types of oxygen sensors:
- Upstream sensors are located before the catalytic converter, directly in the exhaust manifold. These sensors regulate the engine’s air-fuel mixture by constantly monitoring the gasses exiting the engine.
- Downstream sensors are located after the catalytic converter. These sensors assess the effectiveness of the catalytic converter by comparing the amount of oxygen in the exhaust before and after the converter.
Can You Replace Oxygen Sensors Yourself?
Unless you have sufficient automotive knowledge or training, it’s best not to attempt a DIY oxygen sensor replacement.
While replacing a bad oxygen sensor doesn’t require many tools, it can still be tricky. You’ll need an OBD scan tool to identify the faulty sensor that needs to be replaced. Additionally, you should know how to use an oxy-acetylene torch to remove a bad sensor from the exhaust system sensor if it’s stuck due to rust.
If you don’t know your way around these tools and car parts, it’s best to take the vehicle to a repair shop for oxygen sensor replacement.
Get Expert O2 Sensor Replacement with AutoNation Mobile Service
When an oxygen sensor fails, it significantly reduces your car’s engine performance and fuel efficiency. So, it’s important to watch out for the warning signs of oxygen sensor issues mentioned above.
But if driving to a car repair shop seems risky, call AutoNation Mobile Service.
We’re a mobile auto repair and maintenance solution available seven days a week.
The best part?
Our expert mechanics can diagnose and replace your faulty oxygen sensor right from your driveway!
Simply make an appointment online for an oxygen sensor replacement service or other auto repair.