Denso 234-4374 Oxygen Sensor - Upstream or Upstream Right

Denso OE Style Oxygen Sensor 234-4374

Denso 234-4374 is an OE Style heated oxygen sensor built for direct replacement in select Ford, Mazda, Lincoln, and Mercury applications. It is engineered for exact fit and stable signal performance, with vehicle coverage that includes upstream positions on the Ford Escape, Fusion, E-150, E-250, E-350 Super Duty, F-250 Super Duty, F-350 Super Duty, and related models.

This Denso oxygen sensor uses a threaded mounting design, a 4-wire heated configuration, a male connector, and a 15.39-inch wiring harness length. The OE-style construction supports accurate exhaust feedback for vehicles such as the 2005-2010 Ford Escape upstream oxygen sensor application and the 2006-2010 Ford Fusion upstream oxygen sensor application.

Key Features

• OE Style replacement oxygen sensor for direct-fit service
• Heated sensor design for faster operating response
• Specific fit application for confirmed vehicle coverage
• 4-wire layout with male connector
• Threaded mounting type with 0.708-inch thread diameter
• 15.39-inch wiring harness length for listed applications
• Cross-reference part numbers include Bosch 18124 and NTK 22012

Product Details

Denso 234-4374 is manufactured and tested to OE standards for replacement use where precise fit and dependable sensor output matter. The sensor is built with Denso’s aluminum oxide trap layer, which helps protect the ceramic element from silicone and lead contamination, supporting consistent engine management performance and fuel efficiency. This OE Style oxygen sensor is a direct replacement choice for upstream locations on the Ford Escape, Ford Fusion, Mazda Tribute, Mercury Mariner, Mercury Milan, Lincoln Zephyr, and select Ford Super Duty and E-Series vehicles.

Fits 2005-2010 Ford Escape, Upstream. Fits 2006-2010 Ford Fusion, Upstream. Fits 2008-2010 Mazda Tribute, Upstream. Fits 2005-2009 Mercury Mariner, Upstream. Part number 234-4374 is also listed for additional upstream Ford, Mazda, and Mercury applications shown in the fitment data.

Common Issues This Sensor Can Address

• Fault codes related to upstream oxygen sensor performance
• Rough idle or inconsistent air-fuel feedback
• Reduced fuel economy caused by inaccurate exhaust readings
• Delayed sensor response during closed-loop operation
• Replacement needs after contamination or sensor aging

Installation Notes

Confirm the upstream sensor location, connector style, wire count, and thread size before installation. This part is a specific-fit, threaded sensor, so matching the vehicle application and connector orientation is important for proper installation. Use the listed fitment data for the exact year, make, model, and position, including Ford Fusion and Mercury Milan upstream right applications where specified.

Quality Assurance

Denso builds this OE Style oxygen sensor to strict original-equipment standards and tests it for replacement accuracy and first-time fit. The design focuses on reliable sensor response and long-term durability in the exhaust stream.