Delphi ES20104 Oxygen Sensor - Front, Front Left or Front Right

Delphi ES20104 Oxygen Sensor Overview

The Delphi ES20104 is a heated oxygen sensor built for front-position applications on select Ford, Lincoln, Mazda, and Mercury vehicles. It uses a 4-wire design, a round connector, and an 18 x 1.5 mm thread size to match the specified OE-style fitment for the listed applications.

With Delphi’s OE heritage and decades of supplier experience, this oxygen sensor is engineered for accurate exhaust monitoring on vehicles such as the Ford Edge, Ford Fusion, and Lincoln MKZ. The ES20104 is also referenced by part number ES20104 for easy cross-checking during replacement.

Key Features

• Heated oxygen sensor for front exhaust monitoring
• 4-wire configuration with round connector shape
• 18 x 1.5 mm thread size for listed applications
• 400.0 overall length
• Position coverage includes front, front left, and front right depending on vehicle application
• Package contents include the oxygen sensor and instruction sheet

Detailed Description

Delphi ES20104 is a direct-fit style oxygen sensor for a wide range of front sensor locations across 1998-2010 Ford, Lincoln, Mazda, and Mercury models. It is listed for applications including the Ford Escape, Ford F-250 Super Duty, Ford F-350 Super Duty, Ford Fusion, Lincoln MKX, Lincoln MKZ, Mazda CX-9, and Mercury Milan. For vehicles with side-specific front sensor locations, use the application tab to confirm front left or front right placement.

This part cross-references Bosch 15716 for the same application. The ES20104 part number is also commonly searched alongside Ford Fusion front oxygen sensor, Ford Escape front oxygen sensor, and Lincoln MKZ front O2 sensor replacement.

What It Helps Address

• Check engine light related to oxygen sensor performance
• Incorrect air-fuel mixture readings from a failing front sensor
• Reduced fuel control feedback to the engine management system
• Emissions test failures caused by sensor response issues
• Driveability concerns tied to inaccurate exhaust oxygen measurement

Installation Notes and Tips

Confirm the exact front sensor position before ordering, especially on vehicles that use separate front left and front right locations. Verify connector shape, wire count, and thread size against the original sensor before installation. On listed Ford, Lincoln, Mazda, and Mercury applications, match the vehicle year and emission configuration exactly, including notes such as without California Emission System where shown.

For best results, inspect the harness routing and connector condition before installation. The included instruction sheet can help with basic replacement steps, but vehicle-specific access and removal procedures vary by model.

Quality Assurance

Delphi builds aftermarket parts using OE experience and knowledge developed through long-term supplier relationships with major automakers. The ES20104 reflects that OE-based engineering approach for front oxygen sensor replacement on the listed Ford, Lincoln, Mazda, and Mercury applications.