Delphi ES10259 Oxygen Sensor

Delphi ES10259 Oxygen Sensor Overview

The Delphi ES10259 is a heated upstream oxygen sensor built for precise exhaust monitoring and OE-style fitment. It is specified for select Mercedes-Benz applications, including 1986-1993 Mercedes-Benz 300E and other classic inline and V8 models that use a 755 mm overall length.

With Delphi’s OE heritage and sensor engineering experience, this oxygen sensor is built to match the original application requirements for response, connector style, and thread size. The Delphi ES10259 is a direct-fit option for drivers servicing Mercedes-Benz 300E, 300TE, and related models.

Key Features

• Heated oxygen sensor for faster operating temperature and exhaust feedback
• Upstream position for pre-catalyst monitoring
• 3-wire design
• Square and round connector shape
• 18 x 1.5 mm thread size
• 755.0 overall length
• Package contents: oxygen sensor and instruction sheet
• OE-focused engineering from Delphi

Detailed Description

The Delphi ES10259 oxygen sensor is engineered for vehicles that require an upstream heated sensor with a 3-wire configuration and a 755 mm overall length. It is listed for select Mercedes-Benz models, including 1986-1993 Mercedes-Benz 300E, 1988-1993 Mercedes-Benz 300TE, 1988-1992 Mercedes-Benz 300CE, 1988-1991 Mercedes-Benz 300SE, 1988-1991 Mercedes-Benz 300SEL, 1987-1989 Mercedes-Benz 260E, and 1986-1989 Mercedes-Benz 560SL. This part number, ES10259, also cross-references Bosch 13146 for the same application.

Delphi draws on long OE supplier experience to build aftermarket parts around original equipment knowledge and fitment requirements. For Mercedes-Benz 300E oxygen sensor replacement and other compatible Mercedes-Benz applications, ES10259 provides the connector style, thread specification, and sensor layout needed for a proper service replacement.

Common Issues This Sensor Can Address

• Faulty oxygen sensor signal causing incorrect air-fuel feedback
• Check engine light related to upstream sensor performance
• Rough idle or hesitation tied to inaccurate exhaust readings
• Reduced fuel control from a worn heated O2 sensor
• Emissions test failure caused by a degraded sensor

Installation Notes and Tips

• Verify the vehicle uses a 755 mm overall length before ordering.
• Confirm the connector shape and 3-wire configuration match the original sensor.
• Check the 18 x 1.5 mm thread size during removal and installation.
• Install in the upstream location only where specified by the vehicle application.
• Inspect the harness routing and connector condition before final connection.

Quality Assurance

Delphi builds this oxygen sensor using OE experience and supplier knowledge developed over decades of original equipment production. That background supports consistent fitment and sensor design for select Mercedes-Benz applications, including 1986-1993 Mercedes-Benz 300E and related models.