Delphi ES20057 Oxygen Sensor - Rear, Rear Left or Rear Right

Delphi ES20057 Oxygen Sensor Overview

The Delphi ES20057 is a heated oxygen sensor built for rear sensor locations on select Nissan and INFINITI applications. It combines OE-based engineering with a square connector, 4-wire design, and 18 x 1.5 mm thread size for direct-fit replacement needs.

Use this Delphi oxygen sensor when servicing rear, rear left, or rear right positions on vehicles such as the Nissan Altima, Nissan Sentra, Nissan 200SX, Nissan 240SX, and INFINITI Q45. The ES20057 part number is also referenced in OE-style replacement searches for these applications.

Key Features

• Heated oxygen sensor for rear exhaust monitoring
• 4-wire configuration with square connector shape
• 18 x 1.5 mm thread size
• Overall length: 300.0
• Package includes oxygen sensor and instruction sheet
• Fits rear, rear left, and rear right positions depending on vehicle application

Detailed Description

Delphi draws on more than a century of OE experience and supplier knowledge used by major automakers, and that background is reflected in the ES20057 oxygen sensor. This sensor is specified for rear-mounted applications and is listed for 1996-2001 Nissan and INFINITI vehicles, including 1996 Nissan Altima with California Emission System, 1997-1999 Nissan Altima, 1997-1998 Nissan 200SX, 1997-1998 Nissan 240SX, 1997-1998 INFINITI Q45, 1998-1997 Nissan Sentra, and 1999-2001 INFINITI Q45 rear left or rear right positions. The Delphi ES20057 is a practical OE-style replacement for drivers searching by part number or by vehicle fitment.

This part cross-references Bosch 13271 and DENSO Auto Parts 234-4325 for the same application.

Common Issues This Sensor May Address

• Check engine light related to rear oxygen sensor performance
• Fault codes tied to exhaust oxygen monitoring
• Incorrect air-fuel feedback from a worn downstream sensor
• Emissions test failures caused by a degraded rear sensor
• Rough or inconsistent fuel control after sensor aging

Installation Notes and Tips

Confirm the exact position on your vehicle before ordering, since this part is listed for rear, rear left, and rear right locations depending on application. Match the connector shape, wire count, and thread size to the original sensor, and inspect the harness routing and exhaust bung condition before installation. For the correct fit on Nissan Altima, Nissan Sentra, and INFINITI Q45 applications, verify the vehicle’s emission system and build details against the application tab.

Quality Assurance

Delphi builds aftermarket parts using OE heritage and engineering knowledge developed through long-term supplier experience with global automakers. That OE-based approach supports consistent fitment and specification matching for the ES20057 oxygen sensor.