Denso 234-4400 Oxygen Sensor

Denso OE Style Oxygen Sensor 234-4400

Denso 234-4400 is an OE Style heated oxygen sensor built for specific-fit replacement on select Toyota and Lexus applications. It is engineered for direct installation in downstream positions and supports accurate exhaust feedback for drivability and emissions performance.

Key Features

• Heated oxygen sensor with a specific-fit design
• 4-wire configuration with male connector
• Threaded mounting type for OE-style installation
• Wiring harness length: 22.32
• Thread diameter: 0.708
• Built to OE standards for exact replacement fit
• Aluminum oxide trap layer helps protect the ceramic element from silicone and lead contamination

Product Details

The Denso OE Style line focuses on direct replacement parts that match factory fit and function. This oxygen sensor is precision built for the intended application, helping maintain proper exhaust monitoring on vehicles such as the Toyota Prius, Toyota Highlander, Lexus CT200h, and Lexus RX350. Part number 234-4400 is designed for downstream locations, including downstream left, downstream right, and downstream front positions where listed.

This part cross-references Bosch 18018 and NTK 24834 for the same application.

What This Sensor Helps Address

• Check engine light concerns related to oxygen sensor performance
• Incorrect air-fuel feedback from a worn downstream sensor
• Reduced fuel economy caused by inaccurate exhaust readings
• Emissions test failures tied to sensor response issues
• Rough or inconsistent engine operation linked to faulty exhaust monitoring

Installation Notes

• Verify the exact year, make, model, and sensor position before ordering.
• Use the listed specific-fit application data for Toyota Prius, Prius V, Highlander, Sienna, and Lexus CT200h, RX350, and RX450h vehicles.
• Confirm connector style, wire count, and thread size match the original sensor.
• Inspect the exhaust bung and harness routing before installation.
• Clear diagnostic trouble codes after installation and confirm proper sensor operation.

Quality Assurance

Denso manufactures and tests this OE Style oxygen sensor to strict original-equipment standards for fit and performance. The design includes contamination protection for the sensing element, supporting long service life in demanding exhaust environments.