Delphi ES20173 Oxygen Sensor - Rear, Rear Left or Rear Right

Delphi ES20173 Heated Oxygen Sensor Overview

The Delphi ES20173 is a heated oxygen sensor designed for precise emission control in select BMW and Mercedes-Benz models. Engineered with a 4-wire configuration and a round connector, this sensor ensures accurate air-fuel mixture readings for optimal engine performance.

• Heated oxygen sensor with 4 wires for reliable operation
• Round connector shape for secure and proper fitment
• Thread size of 18 x 1.5 mm compatible with specific rear positions
• Overall length of 430.0 mm for correct installation depth
• Includes oxygen sensor and instruction sheet for installation guidance
• Position-specific fitment: rear, rear left, and rear right

Technical Details and Compatibility

The Delphi ES20173 oxygen sensor features a heated design that allows it to reach operating temperature quickly, improving sensor response time and reducing emissions during cold starts. The 4-wire setup supports both the sensor signal and heater circuit, ensuring consistent performance. Its round connector and 18 x 1.5 mm thread size are engineered to fit rear oxygen sensor ports on various BMW and Mercedes-Benz vehicles. The 430 mm overall length accommodates proper sensor placement in the exhaust system, critical for accurate readings.

This sensor is compatible with BMW models such as 525i, 525xi, 528i, 528i xDrive, 528xi, 530i, 530xi, M5, M6, M6 Gran Coupe, and Z4. It also fits Mercedes-Benz models including C32 AMG, C55 AMG, C240, C320, CLK55 AMG, CLK320, CLK500, CLS55 AMG, CLS500, E55 AMG, E320, E500, ML500, R500, SL55 AMG, SL500, and SLR McLaren. The ES20173 is designed for rear oxygen sensor positions, including rear left and rear right, depending on vehicle specifications.

Common Applications and Problem Resolution

• Helps resolve rough idling caused by incorrect air-fuel mixture readings
• Addresses increased emissions and failed emissions tests
• Corrects poor fuel economy related to faulty oxygen sensors
• Eliminates check engine light triggers related to oxygen sensor faults
• Improves engine performance by providing accurate exhaust gas data

Installation Notes and Tips

When installing the Delphi ES20173 oxygen sensor, ensure the vehicle is cooled down to avoid burns. Use the included instruction sheet for guidance on sensor orientation and torque specifications. Verify the sensor’s connector matches the vehicle’s wiring harness to prevent electrical issues. It is recommended to replace oxygen sensors in pairs when applicable to maintain balanced sensor readings across the exhaust system.

Quality Assurance and Warranty

Delphi oxygen sensors undergo rigorous testing to meet OEM standards for durability and accuracy. The ES20173 part number is backed by Delphi’s quality assurance processes, ensuring reliable performance in emission control systems. Warranty coverage details should be confirmed at the point of purchase, as they may vary by distributor or region.