Bosch 13723 Oxygen Sensor - Downstream

Bosch OE Oxygen Sensor for Porsche 911

Bosch Part Number 13723 is an Actual OE Oxygen Sensor built for precise air-fuel-ratio feedback to the ECU. It is a heated narrow-band sensor with a specific fit design for the downstream position on select Porsche 911 models.

Key Features

• Actual OE Oxygen Sensor from Bosch
• Fits 1995-1999 Porsche 911, downstream
• Heated narrow-band sensor for closed-loop fuel control
• Specific-fit design with 4-wire harness and oblong male connector
• Threaded mounting with 18 mm thread diameter and 22 mm hex size
• Wiring harness included for direct replacement use
• Built with high-temperature-resistant materials for demanding exhaust conditions

Detailed Description

Bosch 13723 is a narrow-band heated oxygen sensor engineered to measure exhaust oxygen content and send accurate feedback to the engine control unit. On Porsche 911 applications, this downstream sensor supports stable combustion control and emissions management by helping the ECU maintain the correct air-fuel ratio during normal driving conditions. Bosch’s OE sensor development includes ceramic sensing elements, controlled heater operation, and durable construction for consistent signal response under heat and vibration.

The Bosch Actual OE Oxygen Sensor line reflects decades of original equipment development and brings OE-style performance to the aftermarket. For buyers searching for a Porsche 911 downstream oxygen sensor, Bosch 13723 provides a direct-fit replacement solution with the correct connector style, threaded mount, and harness configuration.

This part cross-references Porsche 99360611801 for the same application.

What It Helps Solve

• Check engine light caused by a failing downstream O2 sensor
• Rich or lean fuel trim readings from inaccurate exhaust feedback
• Slow sensor response during closed-loop operation
• Emissions test failures related to oxygen sensor performance
• Rough combustion control caused by degraded sensor output

Installation Notes and Tips

Fits 1995-1999 Porsche 911, downstream. Confirm the connector shape, 4-wire layout, and 18 mm threaded mounting before installation. Use the correct oxygen sensor socket or 22 mm hex tool, and inspect the exhaust bung threads for damage or corrosion before threading in the replacement sensor.

Quality Assurance

Bosch backs this oxygen sensor with more than five decades of OE development experience. The sensor uses OE-proven design principles, including heated narrow-band operation and durable materials selected for exhaust heat and vibration exposure.