Bosch 13550 Oxygen Sensor - Downstream Right

Bosch Actual OE Oxygen Sensor 13550

Bosch 13550 is a narrow-band heated oxygen sensor built for precise air-fuel-ratio feedback to the ECU. It is a specific-fit replacement for select Audi A4, Audi A4 Quattro, Audi A6, Audi A6 Quattro, and Volkswagen Passat applications with downstream right placement.

Key Features

• Actual OE Oxygen Sensor line from Bosch
• Narrow-band heated sensor for closed-loop fuel control
• Threaded mounting with 18 mm thread diameter and 22 mm hex size
• Specific fit with wiring harness included
• 4-wire design with round connector, male connector gender, and female terminal gender
• Steel finish with metal housing for high-temperature service
• Wiring harness length: 23.3 in; overall length: 27 in

Product Details

Bosch 13550 uses a switching-type oxygen sensing element to report exhaust oxygen content to the engine control unit, helping maintain stable combustion control across changing operating conditions. Bosch developed this sensor line from its original OE oxygen sensor designs and later planar narrowband technology, which supports faster light-off, improved lambda accuracy, and quicker closed-loop operation. For drivers searching for an Audi A4 downstream right oxygen sensor, Audi A6 downstream right O2 sensor, or Volkswagen Passat downstream right replacement, Bosch 13550 provides an OE-style solution backed by Bosch’s long history in oxygen sensor development. This part cross-references Bosch 13550 for the same application.

What It Helps Address

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

Installation Notes and Tips

Install Bosch 13550 in the downstream right position only where listed in the fitment data. Verify the 18 mm thread size, 4-wire configuration, and round connector before installation. Because this is a threaded oxygen sensor, use the correct oxygen sensor socket or wrench and inspect the exhaust bung threads for damage before tightening. Confirm harness routing and connector orientation so the wiring is kept away from heat and vibration.

Quality Assurance

Bosch supplies this Actual OE Oxygen Sensor line with OE-proven design principles, including advanced ceramic sensing elements, optimized heater control, and high-temperature-resistant materials. Bosch 13550 is engineered for consistent operation under thermal and vibration load conditions common in exhaust service.

Compatible Vehicles

• Fits 1998-2000 Volkswagen Passat, downstream right
• Fits 1996-1999 Audi A4, downstream right
• Fits 1996-1999 Audi A4 Quattro, downstream right
• Fits 1998-1999 Audi A6, downstream right
• Fits 1998-1999 Audi A6 Quattro, downstream right
• Fits 1999 Audi A6 Quattro, downstream right