Delphi ES20420 Oxygen Sensor - Rear Left

Delphi ES20420 Rear Left Oxygen Sensor

The Delphi ES20420 is a heated oxygen sensor built for rear left exhaust monitoring on select Lexus applications. It uses a 4-wire design, square connector shape, and 18 x 1.5 mm thread size for a direct-fit replacement on listed vehicles.

Built with OE heritage and decades of supplier experience, this Delphi oxygen sensor is made for accurate exhaust feedback on the rear left position. It is a strong match for Lexus GS350 and Lexus IS250/IS350 applications that require Delphi ES20420 service replacement.

Key Features

• Heated oxygen sensor for rear left placement
• 4-wire configuration with square connector shape
• 18 x 1.5 mm thread size
• Overall length: 1135.0
• Package contents: oxygen sensor and instruction sheet
• OE-focused design backed by Delphi’s aftermarket and original-equipment experience

Detailed Description

Delphi ES20420 is an emission control oxygen sensor intended for rear left exhaust monitoring on specific Lexus models. It is listed for 2014 Lexus GS350 rear left, 2013 Lexus GS350 rear left, 2007-2011 Lexus GS350 rear left, 2006-2013 Lexus IS250 rear left, and 2013 Lexus IS350 rear left. This part number, ES20420, is a practical replacement choice when servicing the rear oxygen sensor circuit on these applications.

This part cross-references Bosch 15126 for the same application. It also cross-references DENSO Auto Parts 234-4518 and 234-4519 for the same application.

What It Helps Address

• Check engine light related to rear oxygen sensor performance
• Incorrect exhaust feedback from a worn heated sensor
• Emissions system faults tied to rear left sensor readings
• Rough or inconsistent fuel control caused by inaccurate sensor data
• Service replacement needs for Lexus GS350, IS250, and IS350 rear left applications

Installation Notes and Tips

Verify the rear left position, connector shape, and thread size before installation. Confirm vehicle year and model against the listed fitment for Lexus GS350, Lexus IS250, and Lexus IS350 applications. Use the included instruction sheet during installation and inspect the exhaust bung and wiring routing before final tightening.

Quality Assurance

Delphi builds this sensor using OE experience and knowledge developed through long-term supply relationships with major automakers. The ES20420 reflects that background in an aftermarket oxygen sensor for listed Lexus rear left applications.