Bosch 18035 Oxygen Sensor - Downstream

Bosch Oxygen Sensor for Honda Fit and Insight

Bosch Engineered Oxygen Sensor 18035 is a narrow-band heated downstream O2 sensor built for precise air-fuel-ratio feedback to the ECU. It supports stable combustion control and emissions management for select Honda Fit, CR-Z, and Insight applications.

Key Features

• Bosch Engineered Oxygen Sensor line with OE-focused design and calibration
• Narrow-band heated oxygen sensor for downstream use
• Specific-fit replacement with 4-wire, pin-terminal configuration
• Threaded mounting with 18 mm thread diameter and 22 mm hex size
• Metal housing with high-temperature-resistant construction
• Wiring harness included for direct replacement service
• Part number 18035 for application matching and catalog lookup

Product Details

Bosch 18035 uses a switching-type narrow-band design to send accurate oxygen content data to the engine control unit. That feedback helps the ECU maintain the proper air-fuel ratio during closed-loop operation, which is important for emissions control and drivability. Bosch’s Engineered Oxygen Sensor line draws on decades of OE development, including advanced ceramic sensing elements and heater control strategies that support faster sensor activity after startup and consistent performance under heat and vibration.

This part cross-references Monroe Shocks & Struts (e.g., 172286, 182286) for the same application. It is a direct-fit oxygen sensor for downstream service on 2015-2020 Honda Fit, 2009-2013 Honda Fit, 2011-2016 Honda CR-Z, and 2010-2014 Honda Insight. The Bosch 18035 is a practical replacement when the original sensor no longer provides stable signal output.

What It Helps Address

• Check engine light related to oxygen sensor performance
• Unstable air-fuel ratio feedback to the ECU
• Reduced closed-loop fuel control accuracy
• Emissions test failures tied to downstream sensor faults
• Slow sensor response after warm-up

Installation Notes

Verify the connector shape, 4-wire layout, and threaded 18 mm mounting before installation. This sensor is specific fit and positioned for downstream applications only. Use proper oxygen sensor service tools and confirm the exhaust threads are clean before threading the sensor into place. Match the vehicle application carefully for Honda Fit, Honda CR-Z, and Honda Insight models listed in the fitment data.

Quality Assurance

Bosch backs this oxygen sensor with more than five decades of OE development in emissions and engine management sensing. The Bosch Engineered Oxygen Sensor 18035 is built to OE-style standards for accurate signal delivery and durable service in demanding exhaust conditions.