Delphi ES20107 Oxygen Sensor - Rear

Rear Heated Oxygen Sensor for GM Applications

Delphi ES20107 is a rear heated oxygen sensor built for precise exhaust monitoring on select Chevrolet, Pontiac, and Oldsmobile vehicles. It uses a 4-wire design with a square connector and 18 x 1.5 mm thread size for direct-fit replacement in the rear sensor position.

Fits 2004-2005 Chevrolet Classic, rear; Fits 2002-2005 Pontiac Grand Am, rear; Fits 2004 Chevrolet Corvette, rear; Fits 2002-2004 Oldsmobile Alero, rear. Delphi ES20107 is a practical replacement when you need accurate downstream oxygen sensor feedback for emissions system operation.

Key Features

• Heated oxygen sensor for rear position use
• 4-wire configuration for modern exhaust monitoring systems
• Square connector shape for OE-style electrical connection
• 18 x 1.5 mm thread size for proper exhaust bung fitment
• 1100.0 overall length for application-specific routing
• Includes oxygen sensor and instruction sheet
• Delphi ES20107 cross-references Bosch 15900 and DENSO Auto Parts 234-4104

Detailed Description

Delphi ES20107 is an emission control sensor engineered for rear oxygen sensor locations on the Chevrolet Classic, Pontiac Grand Am, Chevrolet Corvette, and Oldsmobile Alero. Delphi draws on OE experience and supplier knowledge developed through work with major automakers, and that background is reflected in the sensor’s fit, connector style, and electrical configuration. The heated design helps the sensor reach operating temperature quickly so the engine management system can monitor exhaust conditions efficiently after startup.

This part number, ES20107, is a direct replacement choice for drivers and repair shops servicing rear O2 sensor faults on the listed GM vehicles. It is built around the specified square connector and 18 x 1.5 mm thread size, making it a focused solution for downstream sensor replacement rather than a universal part.

What It Helps Address

• Check engine light related to rear oxygen sensor performance
• Slow or inaccurate downstream exhaust readings
• Failed emissions inspection caused by sensor faults
• Damaged connector or wiring at the rear sensor location
• Restoration of proper fuel control feedback from the exhaust system

Installation Notes and Tips

Verify the rear sensor location before ordering, since this part is specified for the rear position only. Confirm the connector shape, wire count, and thread size against the original sensor before installation. Inspect the exhaust bung threads and wiring route during replacement, and follow the included instruction sheet for vehicle-specific service steps. Delphi ES20107 is listed for 2002-2005 Pontiac Grand Am, 2004-2005 Chevrolet Classic, 2004 Chevrolet Corvette, and 2002-2004 Oldsmobile Alero.

Quality Assurance

Delphi builds aftermarket parts using OE heritage and knowledge developed from supplying top automakers, giving this sensor a specification-driven replacement profile for the listed applications.