Bosch 11-78-7-557-223 Oxygen Sensor Pre-Cat O2 Sensor

The Bosch 11-78-7-557-223 oxygen sensor is a precision-engineered OEM replacement O2 sensor designed for upstream (pre-catalytic converter) installation. This genuine Bosch sensor monitors exhaust gases to provide accurate air-fuel ratio data to the engine control unit, ensuring optimal combustion efficiency, improved fuel economy, and reduced emissions.

Key Features:

• OEM-quality oxygen sensor built to original equipment specifications
• Pre-cat upstream sensor position for emission control monitoring
• Heated sensor design for faster response and reliable performance
• 950mm (37.4 inch) cable length with direct-fit connector
• Bosch part number 0258017124 (LSU 4.9 Lambda sensor)
• Replaces BMW OEM part number 11787557223
• No cutting or splicing required for installation

Bosch invented the oxygen sensor in 1976 and has produced over 1 billion sensors worldwide, making them the industry leader in O2 sensor technology. When your oxygen sensor fails, the engine computer can no longer accurately measure the air/fuel ratio, resulting in poor performance, reduced fuel economy, and increased emissions. Installing a new Bosch oxygen sensor restores proper engine management and helps your vehicle run as efficiently as designed.