Denso 234-4491 Oxygen Sensor - Downstream Left, Downstream Rear or Downstream Right

Denso OE Style Oxygen Sensor 234-4491

Denso 234-4491 is an OE Style heated oxygen sensor built for exact replacement and first-time fit. It is engineered for downstream right applications on select Ford and Lincoln vehicles, including Explorer, Flex, Taurus, MKT, and MKS models.

The OE Style line focuses on direct-fit replacement parts that match original sensor requirements. This Denso oxygen sensor uses a threaded mounting design, a female connector, 4 wires, and a 17.48-inch wiring harness length for a factory-style installation.

Key Features

• Heated oxygen sensor for downstream right applications
• Specific fit design for direct replacement
• 4-wire configuration with female connector
• Threaded mounting type with 0.708 thread diameter
• 17.48-inch wiring harness length
• Built to OE standards for consistent sensor performance
• Aluminum oxide trap layer helps protect the ceramic element from silicone and lead contamination

Product Details

Denso 234-4491 is designed for drivers replacing a downstream oxygen sensor on Ford Explorer, Ford Flex, Ford Taurus, Lincoln MKT, or Lincoln MKS applications. As part of Denso’s OE Style product line, this sensor is precision built to match original equipment dimensions and electrical requirements, helping support accurate exhaust monitoring and proper engine management. This part cross-references Bosch 15718 for the same application.

Common Issues This Sensor Can Address

• Check engine light related to downstream oxygen sensor faults
• Incorrect exhaust oxygen readings affecting fuel control strategy
• Reduced fuel economy caused by a failing heated O2 sensor
• Slow sensor response or contamination-related performance loss
• Emissions test failures tied to sensor malfunction

Installation Notes

• Verify the vehicle position before ordering: downstream right, downstream left, or downstream rear applications are listed separately.
• Confirm connector style, wire count, and harness length against the original sensor.
• Threaded mounting requires proper removal and installation procedures to avoid exhaust thread damage.
• Use the vehicle’s service information for torque and connector routing details.

Quality Assurance

Denso manufactures and tests this oxygen sensor to OE standards for fit and performance. The OE Style design is intended to deliver the correct part and the correct fit for the listed Ford and Lincoln applications, including 2011-2019 Explorer, 2011-2019 Flex, 2011-2019 Taurus, 2011-2019 MKT, and 2011-2016 MKS coverage across the specified positions.