Denso 234-5745 Air / Fuel Ratio Sensor - Upstream

Denso OE-Style Air/Fuel Ratio Sensor

Denso 234-5745 is an OE-style wide-band air/fuel ratio sensor built for direct replacement on select BMW applications. It is engineered for exact fitment, stable signal output, and a first-time fit on upstream locations.

Compatible with BMW X3, BMW X4, BMW 740i, and other listed models, this Denso air/fuel ratio sensor supports accurate exhaust feedback for proper fuel control and emissions system operation.

Key Features

• Wide-band air/fuel ratio sensor for upstream placement
• Specific-fit design for direct replacement installation
• 5-wire configuration with male connector
• 28.86 in. wiring harness length
• Standard replacement grade for OE-style service
• Manufactured and tested to OE standards
• Part number: 234-5745

Product Details

The Denso Air / Fuel Ratio Sensor - OE Style line focuses on exact replacement parts that match original equipment requirements. Denso builds and tests each sensor to strict OE standards, with precision construction intended to deliver the correct fit and reliable performance on the first installation. Part number 234-5745 is a direct-fit, wide-band sensor for upstream use on select BMW models.

This part cross-references Bosch 17000 for the same application. It also cross-references Gates 27053 for the same application.

What This Sensor Helps Address

• Check engine light related to air/fuel ratio sensor performance
• Incorrect fuel trim readings from a failing upstream sensor
• Rough idle caused by inaccurate exhaust feedback
• Poor fuel control from degraded wide-band sensor response
• Emissions faults tied to sensor signal issues

Fitment

• Fits 2011-2017 BMW X3, Upstream
• Fits 2015-2016 BMW X4, Upstream
• Fits 2013-2015 BMW 740i, Upstream
• Fits 2013-2015 BMW 740Li, Upstream
• Fits 2013-2015 BMW 740Li xDrive, Upstream
• Fits 2013-2015 BMW ActiveHybrid 7, Upstream
• Fits 2013-2014 BMW 640i Gran Coupe, Upstream
• Fits 2011-2013 BMW 535i xDrive, Upstream
• Fits 2012-2013 BMW 640i, Upstream

Installation Notes and Quality Assurance

Verify the connector style, wire count, and upstream location before installation. This sensor uses a specific-fit design, so matching the vehicle application is important for proper operation. Confirm the part number 234-5745 against the existing sensor and vehicle catalog before service.

Denso manufactures this sensor to OE standards and tests it for replacement use on the listed BMW applications. The OE-style design is intended to provide the correct fit and function expected from a direct replacement sensor.