Bosch 16508 Oxygen Sensor - Downstream or Downstream Front

Bosch OE Oxygen Sensor for Porsche Boxster

Bosch 16508 is a specific-fit, narrow-band heated oxygen sensor for the 2004 Porsche Boxster in downstream and downstream front locations. It measures exhaust oxygen content and sends air-fuel-ratio data to the ECU to support stable closed-loop fuel control and lower emissions.

Built under Bosch Actual OE Oxygen Sensor standards, this replacement uses a threaded metal housing, 4-wire pin-style connection, and an included wiring harness for direct-fit service on the 2004 Porsche Boxster.

Key Features

• Fits 2004 Porsche Boxster, downstream
• Fits 2004 Porsche Boxster, downstream front
• Bosch part number 16508
• Narrow-band heated oxygen sensor
• Specific-fit replacement with threaded mounting
• 4-wire design with female connector and pin terminals
• 22 mm hex size and 18 mm thread diameter
• Wiring harness included

Actual OE Sensor Line

Bosch Actual OE Oxygen Sensor products are based on Bosch’s long OE development history, including early thimble-style sensors and later planar narrowband designs. The result is a replacement oxygen sensor line focused on accurate lambda measurement, faster sensor response, and reliable heater control under high heat and vibration. Bosch 16508 follows that OE-oriented approach for the Porsche Boxster application.

This part cross-references 98660622800 for the same application.

What It Helps Address

• Check engine light related to oxygen sensor performance
• Incorrect air-fuel ratio readings at the ECU
• Rough closed-loop fuel control after sensor aging
• Emissions test failures tied to downstream sensor faults
• Slow sensor response from heat or contamination damage

Installation Notes

Confirm the downstream or downstream front location before ordering Bosch 16508 for the 2004 Porsche Boxster. The sensor uses an 18 mm thread and 22 mm hex, so the correct oxygen sensor socket or wrench is recommended. Inspect the connector routing and harness length before installation, and verify the threaded mounting surface is clean before tightening.

Quality Assurance

Bosch supplies this oxygen sensor as an OE-style replacement backed by decades of oxygen sensor development and aftermarket support. The design uses high-temperature materials, ceramic sensing elements, and controlled heater operation for consistent performance in demanding exhaust conditions.