Denso 234-5059 Air / Fuel Ratio Sensor - Upstream

Denso OE Style Air/Fuel Ratio Sensor 234-5059

Denso 234-5059 is an OE Style heated air/fuel ratio sensor built for precise replacement and exact fit. It is engineered for direct-fit service on select Mazda applications, including upstream locations on Mazda 6, Mazda 3, Mazda 3 Sport, and CX-5 models.

The OE Style line focuses on replacement parts that match original equipment fit and function, helping simplify service on Mazda 6 and Mazda CX-5 air/fuel sensor applications. This Denso 234-5059 sensor is built for specific fitment, with a 5-wire design, male connector, and 24.49-inch wiring harness length.

Key Features

• Heated air/fuel ratio sensor for upstream placement
• Specific-fit design for direct replacement service
• 5-wire configuration with male connector
• 24.49-inch wiring harness length
• Thread diameter: 0.711
• OE Style replacement for select Mazda emissions control applications

Detailed Description

This Denso air/fuel ratio sensor is manufactured and tested to OE-level standards for accurate replacement fitment and consistent service performance. The part number 234-5059 is listed for upstream use on 2013-2018 Mazda CX-5, 2014-2019 Mazda 6, 2014-2016 Mazda 3, 2014-2016 Mazda 3 Sport, and select 2017-2018 Mazda 3 and Mazda 3 Sport vehicles built in Mexico or Japan. This part cross-references Mazda PE01188G1 and NTK 24369 for the same application.

Use Denso 234-5059 when servicing a Mazda air/fuel ratio sensor location that requires an OE Style, heated, specific-fit replacement with the correct connector and harness length. The design supports direct replacement on the listed Mazda 6, Mazda 3, Mazda 3 Sport, and CX-5 applications without requiring a universal sensor setup.

Vehicle Fitment

• Fits 2014-2019 Mazda 6, Upstream, OE Style
• Fits 2017-2018 Mazda 3, Upstream, Mexico Built; OE Style
• Fits 2017-2018 Mazda 3, Upstream, Fits Japan built vehicles; OE Style
• Fits 2017-2018 Mazda 3 Sport, Upstream, Mexico Built; OE Style
• Fits 2017-2018 Mazda 3 Sport, Upstream, Fits Japan built vehicles; OE Style
• Fits 2013-2018 Mazda CX-5, Upstream, OE Style
• Fits 2014-2016 Mazda 3, Upstream, OE Style
• Fits 2014-2016 Mazda 3 Sport, Upstream, OE Style

Common Repair Uses

• Replacing a failed upstream air/fuel ratio sensor on a Mazda 6
• Restoring proper sensor response on Mazda CX-5 emissions control systems
• Addressing check engine light concerns tied to air/fuel sensor faults
• Correcting drivability issues caused by inaccurate upstream mixture readings
• Servicing OE-style sensor applications on Mazda 3 and Mazda 3 Sport models

Installation Notes and Quality

Confirm connector style, wire count, harness length, and thread diameter before installation. This sensor is specific fit, so matching the listed Mazda year, model, build origin, and upstream position is important for proper service. Denso manufactures and tests these sensors to strict OE standards for replacement accuracy and first-time fit.

No warranty information was provided in the product data.