Delphi ES20319 Oxygen Sensor - Center, Front or Rear

Delphi ES20319 Oxygen Sensor Overview

The Delphi ES20319 is a heated oxygen sensor built for precise exhaust feedback in a wide range of GM applications. It supports accurate air-fuel control for vehicles such as the Chevrolet Impala, Buick Century, and Pontiac Grand Prix, helping maintain proper engine management across front and rear sensor locations.

With Delphi OE heritage behind it, this oxygen sensor reflects more than 100 years of original equipment experience and supplier knowledge used by major automakers.

Key Features

• Heated oxygen sensor design for faster operating temperature
• 4-wire configuration for modern engine control systems
• Square connector shape for application-specific fitment
• 18 x 1.5 mm thread size
• 310.0 overall length
• Includes oxygen sensor and instruction sheet
• Position coverage includes center, front, and rear applications depending on vehicle

Detailed Description

Delphi ES20319 is an OE-style oxygen sensor engineered for direct replacement in select Buick, Chevrolet, Cadillac, GMC, Oldsmobile, and Pontiac vehicles. It is listed for front and rear positions across multiple applications, including 2001-2005 Buick Century front, 2001-2005 Chevrolet Impala front, 2002-2005 Chevrolet Blazer front or rear, and 2001-2003 Pontiac Grand Prix front. This part number, ES20319, is also cross-referenced in the aftermarket under several equivalent numbers for the same application.

As an emission control sensor, it monitors exhaust oxygen content so the engine control module can adjust fuel delivery and maintain proper closed-loop operation. That makes it a practical replacement for drivability concerns on vehicles such as the Chevrolet Monte Carlo, Oldsmobile Alero, and Cadillac DeVille when the original sensor has aged or failed.

What It Helps Address

• Check engine light related to oxygen sensor performance
• Rough idle or inconsistent fuel control from a worn sensor
• Reduced fuel economy caused by inaccurate exhaust feedback
• Failed emissions testing tied to sensor response issues
• Slow sensor switching or degraded heater circuit operation

Installation Notes and Tips

Verify the exact sensor position on your vehicle before ordering, since ES20319 is used in multiple front, rear, and center locations. Confirm connector shape, thread size, and wire count against the original part before installation. For best results, inspect the harness routing and exhaust threads during replacement, and follow the included instruction sheet.

Compatible With select 2000-2005 Buick, Chevrolet, Cadillac, GMC, Oldsmobile, and Pontiac models, including Chevrolet Impala, Monte Carlo, Blazer, and Pontiac Grand Prix applications. This part number is commonly searched as Delphi ES20319 for GM oxygen sensor replacement needs.

Quality Assurance

Delphi builds this sensor using OE heritage and knowledge developed through long-term supplier experience with major automakers. That background supports consistent aftermarket replacement quality for emission control service.