
The oxygen sensor is a critical sensing component in the fuel injection engine control system, as well as a key part in controlling vehicle exhaust emissions, reducing environmental pollution, and improving fuel combustion quality in the engine. Oxygen sensors are installed on the engine's exhaust pipe. If the oxygen sensor fails, the electronic fuel injection system's computer cannot obtain information about the oxygen concentration in the exhaust pipe, leading to an inability to perform feedback control on the air-fuel ratio. This results in increased engine fuel consumption and exhaust pollution, along with symptoms such as unstable idling, misfires, and surging.

Honestly, I've encountered oxygen sensor failures before. You can still drive short-term when it's broken, but never delay repairs. This thing is like the car's 'nose' – if it can't detect exhaust concentration, the ECU starts spraying fuel randomly. Fuel consumption can skyrocket by 30%, and it's common to lose over 100 km per full tank. Once, a client insisted on driving for a month, and the catalytic converter got completely clogged, turning a $300 repair into a $3,000 job. Black smoke from the exhaust is a classic warning sign – check the trouble codes immediately. Also, be alert if you notice sudden power loss on highways.

As a driver who has owned an old car for ten years, I know exactly how it feels. Last time when the oxygen sensor threw an error, the repair shop said I could still drive it, but the fuel tank seemed to leak as the gas consumption skyrocketed. What used to be a weekly refuel turned into needing gas every five days. Even worse, it would definitely fail the annual exhaust emission test, and the excessive emissions would damage the catalytic converter. My neighbor pushed it for three months, and in the end, the engine light stayed on permanently. When they took out the catalytic converter, it was all clogged up. My advice is: it might work for short-distance moves in an emergency, but for daily commutes, it's better not to take the risk.

From an perspective, oxygen sensor failure affects closed-loop air-fuel ratio control. The engine is forced to use backup parameters, which may lead to carbon buildup in the combustion chamber and spark plug fouling. Although the vehicle remains drivable, prolonged operation in this condition can trigger a chain reaction. I once diagnosed a car with idle vibration caused by delayed oxygen sensor signals resulting in an overly rich fuel mixture. Such issues can be easily identified using an OBD code reader, and replacing the sensor with an inexpensive part (costing just over ten dollars) can prevent major potential hazards.

Last week I helped a female colleague with this issue. She noticed the car suddenly became extremely fuel-thirsty, and the accelerator pedal felt sluggish when pressed. The repair shop said the rear oxygen sensor had failed, and the mechanic showed her the blackened exhaust pipe tip. Most critically, the catalytic converter might be totaled - replacing it would cost several thousand. I advised her to immediately stop using cruise control and maintain a steady speed to the repair shop. Short-distance driving is fine, but avoid long highway trips.

From an environmental perspective, it's crucial to remind everyone: a faulty oxygen sensor can cause emissions to exceed standards by tenfold. Data shows that oxygen sensor failure alone can increase HC emissions by 4.5 times. I've observed defective parts removed from repair shops, their surfaces covered in grayish-white deposits. While it doesn't affect starting or driving, it harms both the vehicle and pollutes the environment. Some owners report fuel consumption skyrocketing from 8L to 12L. If the engine warning light stays on, immediate inspection is necessary—never risk major damage for minor savings.


