NTK 25721 Oxygen Sensor - Downstream Rear

Overview of NTK Direct Fit Oxygen Sensor 25721

The NTK Direct Fit Oxygen Sensor 25721 is designed specifically for select Lexus and Toyota models, including the Highlander, RX330, RX350, RX400h, and RX450h. This heated oxygen sensor ensures accurate emissions control and optimal engine performance by providing precise air-fuel mixture data to the vehicle's engine management system.

• Heated oxygen sensor for faster response times
• Specific fit for Lexus and Toyota models listed
• Threaded mounting type with 18mm thread diameter
• Four-wire design for reliable electrical connections
• 25.5-inch wiring harness length for proper installation

Direct Fit Oxygen Sensor Product Line Details

The NTK Direct Fit Oxygen Sensor line is engineered to provide exact replacement sensors that match the original equipment specifications. This product line focuses on precise fitment and reliable performance, reducing installation time and ensuring compatibility with the vehicle’s existing wiring and mounting points. The 25721 sensor maintains the integrity of the emissions system for the specified Lexus and Toyota models.

Technical Description and Features

This oxygen sensor features a heated element that allows it to reach operating temperature quickly, improving sensor response and reducing emissions during cold starts. The sensor’s four-wire configuration supports both the heating element and signal transmission, ensuring accurate data delivery to the engine control unit. With a threaded mounting type and an 18mm thread diameter, the sensor installs securely in the exhaust system. The 25.5-inch wiring harness length provides sufficient reach for proper connection without excess slack.

Common Applications and Problem Resolution

• Helps correct engine misfires caused by faulty oxygen sensor readings
• Reduces rough idling and poor fuel economy linked to sensor failure
• Addresses check engine light triggers related to emissions control
• Improves catalytic converter efficiency by maintaining proper air-fuel ratio
• Prevents increased exhaust emissions due to sensor degradation

Installation Notes and Tips

When installing the NTK 25721 oxygen sensor, ensure the vehicle is cool to avoid burns. Use an oxygen sensor socket or appropriate tool to remove the old sensor carefully. Verify the wiring harness length and connector match the vehicle’s factory setup before installation. Apply anti-seize compound to the sensor threads if recommended by the vehicle manufacturer to facilitate future removal. Tighten the sensor to the specified torque to prevent exhaust leaks.

Quality Assurance and Warranty

NTK oxygen sensors undergo rigorous testing to meet OEM standards for durability and performance. The Direct Fit Oxygen Sensor 25721 is manufactured to provide consistent sensor output and long service life. While specific warranty details may vary, NTK typically offers coverage against defects in materials and workmanship to ensure customer confidence in the product.