Symptoms of a Bad or Failing Oxygen Sensor

oxygen sensor

The oxygen sensor in your vehicle measures the exhaust gases exiting the engine and this information is used by the ECU to determine the air to fuel ratio in your engine in real time. The sensor is located in the exhaust stream and allows the fuel injection and engine timing to work efficiently and assists with emission control. The oxygen sensor transmits the data to the vehicle’s computer to keep the optimal air to fuel to air ratio in your engine. A bad or failing oxygen sensor will have a bad impact on the environment and poor engine performance, so there are a few things to watch out for before your oxygen sensor completely fails.

1. Check Engine Light comes on

The first line of defense is the Check Engine Light. The check engine light will illuminate if you have a bad or failing oxygen sensor. As soon as this light comes on, contact the professionals at YourMechanic for a Check Engine Light inspection service. This light can mean many different things, so it is important to have it looked at by a professional. If you have high mileage on your vehicle, chances are it is a bad oxygen sensor that needs to be replaced.

2. Bad gas mileage

If the oxygen sensor is going bad, the fuel-delivery and fuel-combustion systems will be thrown off. If a bad oxygen sensor disrupts the air to fuel ratio mixture or too much fuel is injected into the engine, the gas mileage will go bad. If you suspect you are filling up your gas tank more often, keep a record of how many gallons you fill up with and how often. If it is more than normal, have the mechanics at YourMechanic check out your oxygen sensor.

3. Rough engine idle and misfires

As your oxygen sensor is going bad, you may notice your vehicle is running rough, misfiring or running irregularly while idling. Since the oxygen sensors output helps control engine timing, combustion intervals, and the air to fuel ratio, a bad sensor can disrupt these engine functions causing a rough or irregular engine idle.

When to replace the sensor

If your vehicle has been manufactured within the past 15 years, your oxygen sensor should be replaced every 60,000 to 90,000 miles. The oxygen sensor is a wear item and does fail over time. This will reduce the level of emissions your vehicle puts into the atmosphere, while keeping your engine running smoothly and properly. As soon as you notice your Check Engine light, poor gas mileage, or an irregular engine idle, book a service online 24/7 at YourMechanic to have your oxygen sensor replaced. This will ensure your vehicle is running smoothly and prolong the life of your engine.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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