Bosch 18253 Oxygen Sensor - Downstream Left

Bosch Wideband Oxygen Sensor for Acura and Honda

Bosch Validated Oxygen Sensor 18253 is a specific-fit, heated wideband A/F oxygen sensor built for precise air-fuel ratio monitoring. It provides the ECU with detailed feedback across the full lambda range, helping maintain accurate mixture control in real-world driving conditions.

Compatible With 2016-2020 Acura MDX, downstream left; 2016-2020 Acura TLX, downstream left; and 2018 Honda Pilot, downstream left. Bosch 18253 is a direct-fit emission control sensor for vehicles that require a wide-band, threaded oxygen sensor with a 4-wire, pin-terminal design.

Key Features

• Wide-band sensor type for continuous air-fuel ratio measurement
• Heated design for faster sensor operation and stable readings
• Specific-fit replacement with threaded mounting
• 4-wire configuration with rectangular female connector
• Wiring harness included with 6.2 in harness length
• Metal housing with 18 mm thread diameter and 22 mm hex size
• OE-focused Bosch Validated Oxygen Sensor line

Product Details

Bosch Validated Oxygen Sensor 18253 uses Bosch wideband A/F technology to deliver detailed feedback to the engine control unit, supporting precise fuel control under changing load and temperature conditions. Bosch pioneered the planar pump-cell wideband design used in modern engine management, and this aftermarket replacement reflects that OE development background. For Acura MDX, Acura TLX, and Honda Pilot applications, this downstream left sensor helps maintain accurate emissions monitoring and air-fuel measurement where the vehicle calls for a wide-band heated oxygen sensor.

This part cross-references Monroe Shocks & Struts (e.g., 172286, 182286) for the same application.

What It Helps Address

• Fault codes related to oxygen sensor performance
• Unstable air-fuel ratio readings
• Reduced fuel economy from inaccurate mixture control
• Emissions test failures tied to sensor response issues
• Driveability concerns caused by slow or inconsistent sensor feedback

Installation Notes

Install Bosch 18253 in the downstream left position using the correct threaded mounting point and verify connector shape, terminal type, and harness routing before installation. Confirm the vehicle application by year, make, model, and sensor position before replacing the original unit. Use proper oxygen sensor service tools for removal and installation to avoid damage to the sensor body or exhaust threads.

Quality Assurance

Bosch draws on more than five decades of OE sensor development, and the Validated Oxygen Sensor line is built to meet the demands of modern engine management systems. Bosch 18253 is engineered as a standard replacement part for the specified Acura and Honda applications.