What symptoms will a car show if the oxygen sensor is broken?

[DeKylie]

A faulty oxygen sensor in a car may cause the following symptoms: 1. Malfunctions: It can lead to increased engine fuel consumption and exhaust pollution, as well as unstable idling, misfires, and surging. 2. Loss of feedback control: The ECU of the electronic fuel injection system will not receive information about the oxygen concentration in the exhaust pipe, thus failing to provide feedback control for the air-fuel ratio. Relevant information about the car oxygen sensor is as follows: 1. Function: The oxygen sensor is used to detect the oxygen concentration in the exhaust and send feedback signals to the ECU, which then adjusts the fuel injection amount to keep the air-fuel ratio near the theoretical value. 2. Working principle: It uses a ceramic sensing element to measure the oxygen potential in the car's exhaust pipe, calculates the corresponding oxygen concentration based on chemical equilibrium principles, and monitors and controls the combustion air-fuel ratio to ensure product quality and compliance with exhaust emission standards.

[Claire]

I recently encountered this issue where the car was clearly not running right. First, the check engine light on the dashboard stayed on constantly. At first, I thought it was a minor problem, but then fuel consumption skyrocketed, with a full tank covering much less distance than before. The car also became very sluggish during acceleration—sometimes even flooring the gas pedal had no effect, and the power drop was severe. At idle or low speeds, the engine would shake, making the ride bumpy and unstable. It even started emitting black smoke or strange odors, with exhaust emissions clearly exceeding standards. This was mainly due to a faulty oxygen sensor, which couldn’t accurately measure the oxygen levels in the exhaust, causing the engine computer to improperly adjust the air-fuel mixture. If left unrepaired, it not only damages the engine but also wastes fuel. Eventually, I went to a professional shop to replace the sensor, and the car returned to normal. For safety, it’s best to address these symptoms as soon as they appear.

[DiAlyssa]

As an average car owner, I think the most common symptom of a faulty oxygen sensor is a sudden increase in fuel consumption, costing more money per kilometer driven. Then the engine warning light keeps coming on to alert you, and the power isn't as good as before—acceleration feels sluggish, especially noticeable on highways. At idle, the car vibrates heavily, feeling like it might stall, and emissions worsen, sometimes with black smoke coming from the tailpipe, polluting the environment. Simply put, it's like the car's nose fails, unable to assess exhaust conditions, causing the engine to improperly adjust the air-fuel mixture. Don't attempt DIY repairs—it's best to take it to a repair shop for inspection. Fixing it can save fuel and money while preventing bigger issues. Addressing it early also reduces environmental harm and ensures overall peace of mind while driving.

[MacGabriel]

As a car enthusiast, oxygen sensor failures exhibit various symptoms: the engine light comes on, fuel consumption increases, power decreases, and idle becomes rough. The core issue is its inaccurate measurement of exhaust oxygen levels, causing the ECU to improperly adjust the air-fuel ratio, leading to incomplete combustion. Common consequences include excessive emissions, black smoke, and engine vibration. After repair, the car's performance improves immediately, driving becomes much smoother.