Why do taxis remove the oxygen sensor?
4 Answers
The reason taxis remove the oxygen sensor: If an electronically controlled fuel injection engine equipped with an oxygen sensor experiences issues such as unstable idle, poor acceleration, increased fuel consumption, or excessive exhaust emissions during operation, and there are no other faults in the fuel supply or ignition system, it is highly likely that the oxygen sensor or related wiring is the problem. Most engine electronic control systems have a self-diagnostic function. When a fault occurs in the oxygen sensor or related components, the computer automatically records the fault details. A specialized decoder can be used to read the fault code and identify the issue. If you suspect that problems like unstable idle or poor acceleration are caused by the oxygen sensor, during maintenance, simply disconnect the oxygen sensor connector. If the engine's fault disappears, it indicates that the oxygen sensor is damaged. If the engine fault persists, further investigation is needed to identify the cause elsewhere.
I've been driving a taxi for over ten years and often hear that fellow drivers unplug the oxygen sensor to save fuel and money. The sensor monitors exhaust emissions, but if it's damaged, replacing a new one can be costly. After unplugging, the engine defaults to running in a rich mixture state, which might save a bit on fuel costs in the short term. After all, we drive long distances every day, and fuel expenses are a major cost. Reducing the frequency of the check engine light also avoids fines. However, I must remind you that this habit increases pollution in the long run and may damage the engine, which is detrimental to the vehicle's lifespan. I've seen many old cars requiring more repairs because of this, ultimately wasting money. Nowadays, we encourage everyone to perform regular maintenance to maintain cost-effectiveness.
As a mechanic with years of experience, I often encounter taxi drivers removing the oxygen sensor. The sensor is responsible for regulating the fuel mixture, and once removed, the system loses feedback, causing the engine to continuously output incorrect signals leading to high emissions. Many drivers believe this can improve throttle response or save fuel, but in reality, it causes more carbon buildup and increases the risk of knocking. If the sensor warning light stays on, repairing it only requires checking the wiring or replacing the part—removing it can lead to greater damage. I also recommend regularly cleaning carbon deposits near the sensor to extend its lifespan and prevent misuse. Higher vehicle emissions are also environmentally unfriendly, and fixing it is not costly while protecting the engine.
I've been paying attention to automotive safety for a long time, and removing the oxygen sensor from taxis is an illegal act. The sensor is a critical component of the emission system. After removal, the car's exhaust exceeds standards, increasing pollution risks, and it can easily lead to engine control disorders and malfunctions. In many places, this is a violation, failing annual inspections and facing fines. From a safety perspective, I advise drivers to replace damaged sensors promptly rather than removing them. If the light comes on, get it checked and repaired immediately to avoid accidents. Proper maintenance of the emission system not only complies with regulations but also ensures more reliable driving, reducing hazards and saving worries.
