Bosch 16139 Oxygen Sensor - Downstream

Bosch Actual OE Oxygen Sensor for BMW

Bosch 16139 is an Actual OE Oxygen Sensor built for downstream monitoring on select BMW applications. It uses a narrow-band heated design to deliver precise air-fuel-ratio feedback to the ECU, helping maintain stable combustion control and emissions performance.

Key Features

• Actual OE Oxygen Sensor from Bosch Actual OE Oxygen Sensor line
• Narrow-band heated sensor for faster closed-loop operation
• Specific fit with threaded mounting and 18 mm thread diameter
• 4-wire design with blade terminals and oblong connector
• Wiring harness included; harness length 18.4 in
• Metal housing with high-temperature-resistant construction
• Downstream application for select BMW 340i, 440i, 540i, 740i, X3, X4, M240i, and related models

Detailed Description

Bosch 16139 is engineered as a standard replacement oxygen sensor for downstream locations on select BMW vehicles, including 2016-2018 BMW 340i and 340i xDrive, 2017-2021 BMW M240i and M240i xDrive, 2017-2020 BMW 440i, 440i Gran Coupe, 440i xDrive, 440i xDrive Gran Coupe, 540i, 540i xDrive, and 740i, plus 2018-2021 BMW X3, 2019-2021 BMW X4, 2017-2020 BMW 740i xDrive, and 2017-2019 BMW 340i GT xDrive and 2018-2019 BMW 640i xDrive Gran Turismo. Bosch’s narrow-band heated sensor design uses advanced ceramic elements and optimized heater control to provide accurate lambda feedback under changing exhaust temperatures and vibration loads. Part number 16139 is also referenced for the same application as 11788611294.

What This Sensor Helps Address

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

Installation Notes and Tips

Confirm the downstream position and connector style before installation. This sensor uses a threaded 18 mm mounting design, a 22 mm hex size, and a 4-wire harness with a male oblong connector. Verify the vehicle application by year, model, and position before replacing Bosch 16139.

Quality Assurance

Bosch has more than five decades of OE oxygen sensor development and supplies OE-proven sensor technology to the aftermarket. The Bosch 16139 follows that OE-focused engineering approach for consistent signal accuracy and durable operation in demanding exhaust conditions.