Delphi ES20101 Oxygen Sensor - Rear

Delphi ES20101 Rear Oxygen Sensor

Restore accurate exhaust feedback with this Delphi heated oxygen sensor for rear-position applications. Built from Delphi’s OE experience and supplier knowledge, it is a direct-fit replacement for select Subaru models, including the Impreza and Forester.

• Heated oxygen sensor for rear placement
• 4-wire design with square connector shape
• 18 x 1.5 mm thread size
• Overall length: 465.0
• Package contents: oxygen sensor and instruction sheet

Fitment Details

Compatible with 1999-2004 Subaru Impreza, rear, and 1999-2003 Subaru Forester, rear. This Delphi ES20101 oxygen sensor is a fitment-based replacement for rear sensor service on Subaru Impreza and Subaru Forester applications.

This part cross-references Bosch 13469 for the same application.

What It Helps Address

• Check engine light related to rear oxygen sensor performance
• Incorrect exhaust oxygen readings reported to the engine control system
• Fuel trim issues caused by a worn or slow-responding sensor
• Emissions test failures tied to sensor degradation
• Rougher drivability from inaccurate air-fuel feedback

Installation Notes

Verify rear sensor placement, connector shape, thread size, and wire count before installation. Inspect the harness routing and exhaust bung condition, and compare the original sensor length to the Delphi ES20101 before fitting. Use proper oxygen sensor service tools to avoid damaging the sensor or exhaust threads.

Quality Assurance

Delphi builds aftermarket parts using OE heritage and technical knowledge developed through long-term supplier experience with major automakers. The ES20101 reflects that background in a rear heated oxygen sensor replacement for Subaru Impreza and Subaru Forester applications.