NTK 27057 Air / Fuel Ratio Sensor - Upstream

Overview of NTK Direct Fit 5-Wire A/F Sensor 27057

The NTK Direct Fit 5-Wire A/F Sensor 27057 is designed specifically for select Mercedes-Benz models, including the E250, GLE300d, GLK250, ML250, and S350. This heated air/fuel ratio sensor ensures precise monitoring of the air-fuel mixture to support optimal engine performance and emissions control.

• Heated sensor type for faster response times
• 5-wire configuration for accurate signal transmission
• Specific fit for Mercedes-Benz E250, GLE300d, GLK250, ML250, and S350
• Thread diameter of 18 mm and thread length of 0.38 inches
• 29.5-inch wiring harness length for convenient installation
• No mounting bracket included

Details on the Direct Fit 5-Wire A/F Sensor Product Line

The Direct Fit 5-Wire A/F Sensor line by NTK is engineered to provide precise air/fuel ratio measurements with a direct replacement design. This product line focuses on compatibility and ease of installation by matching OEM specifications, including wiring harness length and thread dimensions. The 5-wire heated sensor design enhances durability and responsiveness, making it suitable for emission control systems in specific Mercedes-Benz vehicles.

Technical Description and Specifications

This NTK air/fuel ratio sensor features a heated sensor element that allows it to reach operating temperature quickly, improving sensor response and reducing emissions during cold starts. The 5-wire configuration supports accurate data transmission to the engine control unit (ECU). With a thread diameter of 18 mm and a thread length of 0.38 inches, this sensor fits securely into the designated mounting location. The wiring harness length of 29.5 inches provides sufficient reach for proper connection without excess slack. Note that this sensor does not include a mounting bracket, so installation will rely on the vehicle's existing hardware.

Applications and Common Issues Addressed

• Restores accurate air/fuel ratio readings for Mercedes-Benz E250, GLE300d, GLK250, ML250, and S350
• Helps resolve engine performance problems related to incorrect fuel mixture
• Reduces emissions by ensuring proper sensor feedback to the ECU
• Addresses check engine light triggers related to faulty A/F sensors
• Improves fuel efficiency by maintaining optimal combustion conditions

Installation Notes and Tips

Installation of the NTK 27057 sensor requires matching the sensor thread and wiring harness to the vehicle’s original equipment. Ensure the sensor threads are clean and free of debris before installation. The 29.5-inch wiring harness length allows for straightforward connection without modification. Since no mounting bracket is included, use the vehicle’s existing bracket or mounting point. It is recommended to use anti-seize compound on the threads to prevent seizing and facilitate future removal.

Quality Assurance and Warranty

NTK sensors are manufactured to meet strict quality standards and OEM specifications. The Direct Fit 5-Wire A/F Sensor 27057 undergoes rigorous testing to ensure reliable performance and durability. While specific warranty details are not provided here, NTK typically offers limited warranties covering defects in materials and workmanship. Consult the product packaging or NTK documentation for exact warranty terms.