Denso 234-9143 Air / Fuel Ratio Sensor - Upstream, Upstream Left or Upstream Right

OE Style Air/Fuel Ratio Sensor for Lexus and Toyota

Denso 234-9143 is an OE Style heated air/fuel ratio sensor built for direct replacement on select Lexus and Toyota applications. It is engineered for exact fitment, with a specific-fit design and a 4-wire configuration for clean integration on upstream sensor locations.

The Denso OE Style line focuses on replacement parts that match original equipment standards for fit and function. For buyers searching for a Lexus IS300 upstream left air/fuel ratio sensor or a Toyota 4Runner upstream right sensor, this part number provides a direct-match option backed by Denso’s OE-oriented manufacturing approach.

Key Features

• Part number 234-9143
• Heated air/fuel ratio sensor design
• Specific fit for listed Lexus and Toyota applications
• 4-wire sensor configuration
• Wiring harness length: 9.92
• Regular grade type
• OE Style replacement for upstream sensor locations

Detailed Product Overview

Denso 234-9143 is designed for drivers replacing a failing upstream air/fuel ratio sensor on vehicles such as the Lexus IS300, Lexus IS350, Lexus RC350, Lexus RC F, and Toyota 4Runner. It also covers additional Lexus and Toyota fitments across 2014-2024 model years, including upstream left and upstream right positions where specified. The sensor is precision-built to match the original application, helping ensure proper connector alignment and first-time fit.

This part cross-references NTK 24828 and 24833 for the same application.

What This Sensor Helps Address

• Check engine light related to air/fuel ratio sensor faults
• Rough idle caused by inaccurate exhaust oxygen feedback
• Fuel trim issues from a worn upstream sensor
• Delayed or unstable sensor response during closed-loop operation
• Emissions test failures tied to sensor performance

Installation Notes and Tips

• Confirm the exact year, make, model, and sensor position before ordering.
• Match the upstream left, upstream right, or upstream location listed for your vehicle.
• Inspect the harness routing and connector condition before installation.
• Clear diagnostic trouble codes after installation and verify live data response.
• Use the vehicle service procedure for torque and connector handling.

Quality Assurance

Denso manufactures and tests this OE Style sensor to original-equipment standards for replacement accuracy and fit consistency. The 234-9143 is built as a direct-fit sensor for the listed Lexus and Toyota applications, supporting dependable installation and OE-level replacement expectations.