NTK 25659 Oxygen Sensor - Downstream, Downstream Left or Downstream Right

Direct Fit Oxygen Sensor for Porsche Applications

NTK Direct Fit Oxygen Sensor 25659 is a heated, specific-fit replacement built for downstream use on select Porsche models. It is engineered with OE-style form, function, and connector fitment to support accurate exhaust monitoring on Porsche Cayenne, Boxster, Cayman, and 911 applications.

Key Features

• Heated oxygen sensor for downstream exhaust placement
• Specific-fit design for direct replacement installation
• 4-wire configuration with 30.5 in. wiring harness length
• 18 mm threaded mounting type
• OE-equivalent design for select Porsche Cayenne, Boxster, Cayman, and 911 models
• NTK part number 25659 for catalog and cross-reference lookup

Product Details

NTK is part of the NGK family of products and focuses on oxygen sensor technology for import and domestic vehicles. The Direct Fit Oxygen Sensor line is built to streamline application coverage while maintaining OE-style fit, form, and function. Part number 25659 uses ceramic-based sensor technology developed under NTK’s manufacturing expertise and is tested during production to meet or exceed OE specifications for quality and reliability.

This sensor is designed for downstream positions on select Porsche Cayenne, Porsche Boxster, Porsche Cayman, and Porsche 911 models. It supports long-tail search needs such as downstream oxygen sensor for 2005-2012 Porsche Boxster, downstream right oxygen sensor for 2006-2012 Porsche Cayman, and direct fit oxygen sensor for 2010-2011 Porsche 911. This part cross-references Bosch (e.g., 16147, 16810) for the same application.

What It Helps Address

• Check engine light related to oxygen sensor performance
• Fault codes tied to downstream sensor response
• Incorrect air-fuel monitoring feedback from a worn sensor
• Emissions test failures caused by sensor degradation
• Slow or inconsistent exhaust oxygen readings

Installation Notes and Tips

Fits 2015-2017 Porsche Cayenne, downstream; 2005-2012 Porsche Boxster, downstream right and downstream left; 2006-2012 Porsche Cayman, downstream right and downstream left; 2010-2011 Porsche 911, downstream right and downstream left; and 2007-2008 Porsche 911, downstream right and downstream left. Confirm the sensor position, connector routing, and thread size before installation. The threaded mounting design and specific-fit harness help support a direct replacement on the listed Porsche applications.

Quality Assurance

NTK manufactures oxygen sensors with OE-focused engineering and extensive production testing to support reliable performance. As a major original equipment oxygen sensor supplier, NTK backs this product line with application-specific design and manufacturing controls intended to meet OE-level expectations.