Denso 234-4809 Oxygen Sensor - Downstream, Downstream Left or Downstream Right

Denso OE Style Oxygen Sensor 234-4809

Denso 234-4809 is an OE Style heated oxygen sensor built for specific-fit replacement on select Audi, Porsche, Volkswagen, Bentley, and related applications. It is engineered for direct downstream service, with a threaded mounting design and a 4-wire male connector for a factory-style connection.

For drivers searching for a downstream oxygen sensor for Volkswagen Touareg, Audi A4 Quattro, or Porsche Cayenne, this Denso sensor is built to match the original fit and electrical layout. The 234-4809 part number is also listed across multiple OE and aftermarket cross references for the same application.

Key Features

• OE Style replacement oxygen sensor for specific-fit applications
• Heated sensor design for faster operating response
• 4-wire configuration with male connector
• Threaded mounting type with 0.708 in. thread diameter
• 67.32 in. wiring harness length
• Built to strict OE standards for exact replacement fit
• Uses Denso’s aluminum oxide trap layer to help protect the ceramic element from silicone and lead contamination

Detailed Description

Denso OE Style oxygen sensors are manufactured and tested to OE-level standards for direct replacement performance. This sensor is designed for downstream placement and specific-fit installation, making it a practical choice when replacing a worn or slow-responding sensor on vehicles such as the Audi A8 Quattro, Volkswagen Phaeton, and Porsche Cayenne. The Denso 234-4809 is engineered for first-time fitment and consistent electrical connection, helping restore accurate exhaust feedback to the engine management system.

The OE Style product line focuses on factory-matched replacement parts, and this sensor follows that approach with the correct connector style, harness length, and threaded mount. This part cross-references Bosch 16034 and NTK 25604 for the same application.

What This Sensor Helps Address

• Check engine light related to oxygen sensor performance
• Slow or inaccurate downstream exhaust readings
• Rough fuel control caused by aging sensor output
• Reduced fuel economy from incorrect air-fuel feedback
• Contamination-related sensor degradation from silicone or lead exposure

Installation Notes and Tips

• Verify the vehicle’s downstream sensor location before ordering; fitment includes downstream, downstream left, and downstream right positions depending on application.
• Confirm connector style, wire count, and thread diameter against the original sensor.
• Inspect the exhaust bung threads before installation to ensure proper seating.
• Use the vehicle’s service information for torque and routing specifications.
• Fits 2005-2006 Audi A4 Quattro, downstream right; Fits 2004-2006 Audi TT Quattro, downstream left; Fits 2003-2006 Porsche Cayenne, downstream; Fits 2004-2006 Porsche Cayenne, downstream left; Fits 2004-2006 Volkswagen Phaeton, downstream; Fits 2004-2006 Volkswagen Touareg, downstream left; Fits 2005 Audi A4, downstream right; Fits 2002-2005 Volkswagen Golf, downstream; Fits 2002-2004 Volkswagen Jetta, downstream; Fits 2002-2004 Volkswagen Passat, downstream; Fits 2004 Volkswagen R32, downstream left; Fits 2005-2009 Audi A8 Quattro, downstream; Fits 2015 Bentley Continental, downstream.

Quality Assurance

Denso manufactures this oxygen sensor to strict OE standards and tests it for exact replacement fit and performance. The OE Style line is built to deliver the correct part and fit for the listed applications, including 2015 Bentley Continental, 2005-2009 Audi A8 Quattro, and 2003-2006 Porsche Cayenne.