What is the O2 sensor?

Every new car, and most cars produced after 1980, has at least one oxygen sensor. Its job is to help the engine keep a certain air-to-fuel ratio that balances power, fuel economy and emissions. The O2 sensor checks the amount of oxygen in the exhaust, compared to the amount in the air. It feeds that information to the engine computer, which then adjusts fuel and air intake.

Like most auto parts, the O2 sensor has a life span. Depending on the kind of sensor, it is typically from 30,000 miles to 100,000 miles. If your O2 sensor is failing, you may notice:

  • Warning light on dashboard
  • Sootier exhaust
  • Lower gas mileage
  • Hesitation when you step on the gas
  • Stalling
  • Rough idling

If you notice these symptoms, bring your car or truck to any of our stores for inspection. If you need an oxygen sensor replacement, we can price it exactly for you. While you're there, we'll also make sure your tires have the right air pressure, for safety and fuel economy, free.

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