Denso 234-4448 Oxygen Sensor - Downstream

Denso 234-4448 Oxygen Sensor for OE-Style Replacement

Denso 234-4448 is a heated oxygen sensor built to OE-style specifications for direct replacement in select Hyundai and Kia applications. It is engineered for exact fitment, stable signal performance, and dependable exhaust monitoring in downstream locations.

For drivers servicing a 2011-2014 Kia Optima or select 2011 Hyundai Sonata models, this Denso oxygen sensor supports accurate air-fuel feedback and helps maintain proper engine operation. The OE Style line is designed around first-time fitment and factory-like replacement dimensions.

Key Features

• Heated oxygen sensor for downstream exhaust monitoring
• Specific-fit design for direct replacement applications
• 4-wire configuration with female connector
• Threaded mounting type with 0.708 in. thread diameter
• Wiring harness length: 20.08 in.
• Built to strict OE standards for fit and function
• Aluminum oxide trap layer helps protect the ceramic element from silicone and lead contamination

OE Style Design Details

Denso’s OE Style product line focuses on replacement parts that match factory requirements for fit, connector style, and sensor operation. The Denso 234-4448 uses a heated sensing design and a specific-fit configuration to simplify replacement on the correct downstream exhaust location. This part number is commonly searched for Hyundai Sonata downstream oxygen sensor and Kia Optima downstream oxygen sensor applications.

This part cross-references Bosch 18046 for the same application.

Vehicle Fitment

• Fits 2011-2014 Kia Optima, downstream, OE Style
• Fits 2011-2013 Kia Optima, downstream, excluding California; OE Style
• Fits 2011 Hyundai Sonata, downstream, to 03/21/2011; OE Style
• Fits 2011 Hyundai Sonata, downstream, exc. Calif.; to 03/21/2011; OE Style
• Fits 2011 Hyundai Sonata, downstream, to 11/15/2010; OE Style

Common Issues This Sensor Helps Address

• Check engine light related to oxygen sensor performance
• Incorrect downstream exhaust readings
• Reduced fuel economy caused by faulty sensor feedback
• Rough engine operation tied to inaccurate air-fuel control
• Emissions test failures caused by a worn sensor

Installation Notes

Confirm the connector style, wire count, and threaded mounting location before installation. This is a specific-fit downstream sensor, so match the vehicle build date and emissions notes carefully, especially for 2011 Hyundai Sonata and California-excluded Kia Optima applications. Use the part number 234-4448 to verify the correct OE-style replacement before installation.

Quality Assurance

Denso manufactures and tests this oxygen sensor to OE standards for consistent replacement quality and reliable fit. The sensor’s contamination-resistant design supports long-term durability in demanding exhaust environments.