Lambda Sensor - Bosch - 0258017355

A Lambda sensor, also known as an oxygen sensor (O2 sensor), measures the amount of unburned oxygen in the exhaust gases. This information is crucial for the engine's control unit (ECU) to adjust the fuel-air mixture for optimal combustion, efficiency, and emissions control.

It ensures your engine's fuel system operates efficiently, reduces harmful emissions by supporting the catalytic converter, and helps maintain optimal engine performance. Using a quality sensor like this Bosch unit contributes to better fuel economy and compliance with environmental standards.

The 490 mm refers to the total length of the sensor assembly, including the wiring. The 5 circuits indicate the number of internal connections within the sensor, typically including heating elements and signal/reference pathways, allowing for precise and rapid measurements.

Bosch designs this specific lambda sensor for a long service life, with a recommended replacement interval of 250,000 km. However, performance can degrade over time, and it may need replacement sooner if symptoms of failure appear or if diagnostic codes are triggered.

While possible with the correct tools and technical knowledge, installation involves working with exhaust systems and electrical connections. It is highly recommended to have this part installed by a qualified mechanic to ensure correct fitment and function, and to avoid potential damage or safety hazards.

This sensor is compatible with various Mercedes-Benz and Smart models. It also shares OEM references with Aston Martin vehicles (JY539F472AA, JY539F472AB). Always double-check fitment using a vehicle lookup tool or by consulting with a parts specialist.

A failing lambda sensor can lead to increased fuel consumption, poor engine performance (rough idling, hesitation), increased emissions, and illuminate the 'Check Engine' light on your dashboard. In severe cases, it can also damage the catalytic converter.

Ensure the sensor is correctly installed and the electrical connector is securely fastened. Inspect wiring for damage. If the sensor is new, the code might indicate a faulty sensor or an issue with the ECU or exhaust system (e.g., leak).

A failing lambda sensor can cause the engine to run inefficiently. Verify sensor function with diagnostic tools. Check for exhaust leaks and ensure other engine components (spark plugs, air filter) are in good condition.

Incorrect air-fuel mixture due to a faulty sensor can lead to drivability issues. Confirm the sensor is the correct part number for the vehicle and has been installed properly. Scan for other related engine codes.

A degraded lambda sensor can prevent the catalytic converter from operating efficiently. Ensure the sensor is functioning correctly and replace if necessary. Also, check for other emissions-related issues like vacuum leaks or catalytic converter failure.