Denso 234-4309 Oxygen Sensor - Downstream

Denso OE Style Oxygen Sensor 234-4309

Denso 234-4309 is an OE Style heated oxygen sensor built for specific-fit replacement on select Nissan applications. It is engineered for the downstream position on 2002-2003 Nissan Altima and 2002-2003 Nissan Sentra, helping restore accurate exhaust feedback for proper fuel control and emissions monitoring.

Key Features

• OE Style replacement from Denso for direct-fit service
• Heated oxygen sensor design for faster operating response
• Specific fit with threaded mounting and male connector
• 4-wire configuration with 18.50-inch wiring harness length
• Thread diameter: 0.708 in.
• Downstream sensor application for select Nissan Altima and Nissan Sentra models

Product Details

Denso’s OE Style sensor line is built and tested to OE-level standards for accurate replacement fitment and dependable signal performance. Part number 234-4309 uses a precision-built, specific-fit design so the sensor matches the original mounting and electrical connection on the listed Nissan vehicles. The heated sensor design helps the unit reach operating temperature efficiently, while Denso’s aluminum oxide trap layer helps protect the ceramic element from silicone and lead contamination for longer service life and stable engine management.

This part cross-references Bosch 15518 and NTK 24407 for the same application. Compatible With 2002-2003 Nissan Altima, downstream and 2002-2003 Nissan Sentra, downstream. Denso 234-4309 is a direct replacement choice for drivers searching for a downstream oxygen sensor for 2002-2003 Nissan Altima or 2002-2003 Nissan Sentra.

Common Issues This Sensor Can Address

• Check engine light related to oxygen sensor performance
• Incorrect air-fuel mixture readings from a worn downstream sensor
• Reduced fuel economy caused by inaccurate exhaust feedback
• Emissions test failures tied to sensor response or signal degradation
• Rougher engine operation when the exhaust monitoring system is not reading correctly

Installation Notes and Tips

Verify the connector style, thread diameter, wire count, and downstream location before installation. Because this is a specific-fit sensor, compare the original part to Denso 234-4309 and confirm the harness length and threaded mounting match the vehicle’s factory setup. Inspect the exhaust bung and wiring routing before installation to help ensure a proper seal and clean connection.

Quality Assurance

Denso manufactures this OE Style oxygen sensor to strict original-equipment standards and tests each design for fit and performance consistency. The sensor’s contamination-resistant trap layer adds protection to the sensing element, supporting reliable operation in demanding exhaust conditions.