Bosch 16138 Oxygen Sensor - Downstream

Bosch Actual OE Oxygen Sensor for BMW and Mini

Bosch 16138 is an actual OE oxygen sensor built for downstream monitoring on select BMW and Mini applications. It uses a narrow-band heated design to deliver accurate air-fuel-ratio feedback to the ECU, supporting stable closed-loop operation and emissions control.

Key Features

• Actual OE Oxygen Sensor from Bosch
• Narrow-band heated sensor design
• Specific fit with threaded mounting
• 4-wire layout with blade terminals and rectangular connector
• Wiring harness included with 21.9 in harness length
• Metal housing with 22 mm hex size and 18 mm thread diameter
• Downstream application for select BMW X1, BMW X2, Mini Cooper, Mini Cooper Clubman, and Mini Cooper Countryman models

Product Details

Bosch 16138 is part of the Bosch Actual OE Oxygen Sensor line, a product line focused on OE-style replacement sensors built from Bosch’s long-running oxygen sensor development. Bosch uses ceramic sensing elements, controlled heater operation, and high-temperature materials to maintain consistent signal output under heat and vibration. For BMW X1, BMW X2, Mini Cooper, Mini Cooper Clubman, and Mini Cooper Countryman downstream service, this sensor provides the signal quality needed for accurate fuel control and emissions monitoring.

This part cross-references 11788604889 for the same application.

What It Helps Address

• Check engine light related to downstream oxygen sensor performance
• Incorrect air-fuel ratio feedback to the ECU
• Slow closed-loop response after sensor aging
• Emissions test failures tied to sensor signal degradation
• Rough combustion control caused by inaccurate exhaust oxygen readings

Installation Notes

Compatible With 2017-2024 Mini Cooper Countryman, downstream; 2018-2023 BMW X2, downstream; 2014-2021 Mini Cooper, downstream; 2016-2020 Mini Cooper Clubman, downstream; and 2016-2019 BMW X1, downstream. Verify connector shape, thread size, and harness routing before installation. The sensor is heated and uses a threaded mount with a 22 mm hex, so proper removal tools and anti-seize practices should follow the vehicle service procedure.

Quality Assurance

Bosch backs this oxygen sensor with OE development experience spanning more than five decades. The design reflects Bosch’s original oxygen sensor engineering and later planar narrowband advancements, with a focus on accurate signal output and durable operation in demanding exhaust conditions.