Denso 234-9012 Air / Fuel Ratio Sensor - Upstream Rear or Upstream Right

Denso OE Style Air/Fuel Ratio Sensor

Denso 234-9012 is an OE Style heated air/fuel ratio sensor built for exact replacement and first-time fit. It is a specific-fit sensor with a 4-wire design, male connector, and 7.09-inch wiring harness length for direct service on select Toyota Sienna applications.

For drivers searching for a Toyota Sienna upstream air/fuel ratio sensor, this Denso OE Style part number 234-9012 follows the original equipment approach to fit and function. It is made to match the application closely, helping restore accurate exhaust feedback to the engine control system.

Key Features

• OE Style replacement for select Toyota applications
• Heated sensor design for faster operating readiness
• Specific fit for direct application matching
• 4-wire configuration with male connector
• 7.09-inch wiring harness length
• Thread diameter: 0.711
• Cross-reference: Bosch 13737

Product Details

Denso 234-9012 is an emission control sensor engineered to replace the original air/fuel ratio sensor with the correct fit and connector style. Denso builds and tests these sensors to OE standards, and the OE Style line focuses on accurate replacement dimensions and dependable installation on the intended vehicle. This part is listed for 2007-2010 Toyota Sienna, upstream right, and 2004-2006 Toyota Sienna, upstream rear.

Use this sensor when servicing a Toyota Sienna with a fault in the upstream air/fuel monitoring circuit. The correct sensor response helps the engine management system read exhaust oxygen content and adjust fuel delivery more precisely. Part number 234-9012 is also referenced against Delphi ES10935 for the same application.

What It Helps Address

• Check engine light related to air/fuel ratio sensor performance
• Rough idle caused by inaccurate exhaust feedback
• Fuel trim issues from a slow or failing upstream sensor
• Poor drivability from incorrect air/fuel mixture correction
• Emission test failures tied to sensor malfunction

Installation Notes

Verify the connector, wire count, thread diameter, and sensor position before installation. This specific-fit sensor is intended for the listed Toyota Sienna upstream locations: 2007-2010 Toyota Sienna, upstream right, and 2004-2006 Toyota Sienna, upstream rear. Confirm the vehicle’s original sensor layout and routing before replacing the part.

Quality Assurance

Denso manufactures and tests this OE Style sensor to strict original-equipment standards for replacement accuracy and fit consistency. The brand’s OE-focused approach supports proper application matching for the Toyota Sienna and related listed interchange references.