NTK 21550 Oxygen Sensor - Downstream

Overview of NTK Direct Fit Oxygen Sensor 21550

The NTK Direct Fit Oxygen Sensor 21550 is designed specifically for select Buick, Chevrolet, Oldsmobile, and Pontiac models. 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 sensor type for faster response times
• Specific fit for Buick Achieva, Chevrolet Cavalier, Oldsmobile Cutlass, Pontiac Grand Am, Skylark, and Sunfire
• 67.75-inch wiring harness length for proper installation
• Threaded mounting type with 18mm thread diameter
• Four-wire configuration for reliable signal transmission

Details on the Direct Fit Oxygen Sensor Line

The NTK Direct Fit Oxygen Sensor line is engineered to provide exact replacement sensors tailored to specific vehicle applications. This ensures compatibility and reduces installation time by matching OEM specifications. The 21550 part number belongs to this line, offering a direct fit solution for emission control systems in various GM models.

Product Features and Specifications

This oxygen sensor features a heated element that allows it to reach operating temperature quickly, improving sensor accuracy and reducing emissions during cold starts. The 67.75-inch wiring harness length provides sufficient reach for proper connection without excess slack. Its threaded mounting type with an 18mm diameter ensures secure installation in the exhaust system. The four-wire design supports both the sensor signal and heater circuit, maintaining consistent performance.

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 emission control faults
• Improves catalytic converter efficiency by providing accurate air-fuel data
• Prevents increased exhaust emissions due to sensor degradation

Installation Notes and Tips

When installing the NTK 21550 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. Apply anti-seize compound to the threads if recommended by the vehicle manufacturer to facilitate future removal. Confirm proper torque specifications during installation to avoid damage.

Quality Assurance and Warranty

NTK oxygen sensors are manufactured to meet or exceed OEM standards for durability and performance. The Direct Fit Oxygen Sensor 21550 undergoes rigorous testing to ensure reliable operation within the specified Buick, Chevrolet, Oldsmobile, and Pontiac models. Warranty coverage details should be confirmed with the product documentation or supplier.