NTK 25649 Oxygen Sensor

Direct-Fit Heated Oxygen Sensor

NTK Oxygen Sensor 25649 is a direct-fit, heated oxygen sensor built for specific applications with threaded mounting and a 4-wire design. It is engineered for accurate exhaust feedback and OE-style fitment on select Volkswagen and Bentley applications.

Key Features

• Direct-fit replacement for specific applications
• Heated oxygen sensor design for faster operating response
• 4-wire configuration with threaded mounting
• 18 mm thread diameter
• 18.25 in. wiring harness length
• OE-equivalent design noted in fitment data

Detailed Description

NTK 25649 is part of the Direct Fit Oxygen Sensor line, a product family focused on application-specific coverage and OE-style replacement. NTK draws on its ceramics expertise and original equipment sensor manufacturing background to produce oxygen sensors with controlled ceramic construction, fit, form, and function that align with OE specifications. This part number is used across select Volkswagen Beetle and Jetta applications, as well as Bentley Arnage applications, including upstream, downstream, and intermediate locations listed in the fitment data.

This part cross-references Bosch (e.g., 16332, 16392) for the same application.

What It Is Used For

• Replacing a worn or slow-responding oxygen sensor
• Restoring exhaust gas feedback to the engine management system
• Addressing sensor-related fault codes tied to mixture control
• Correcting drivability issues caused by inaccurate oxygen readings
• Supporting emissions system performance on compatible applications

Installation Notes and Tips

Verify the sensor position, connector style, wire count, and thread size before installation. This application uses a threaded mounting design, so confirm the exhaust bung and lead length match the original sensor routing. Use the fitment notes to match the correct Volkswagen Beetle, Volkswagen Jetta, or Bentley Arnage application and position before ordering.

Quality Assurance

NTK states that its oxygen sensors are extensively tested during manufacturing to meet or exceed OE specifications. The brand is part of the NGK family and is recognized as a major original equipment oxygen sensor supplier.