Bosch 13552 Oxygen Sensor - Downstream Left

Bosch Actual OE Oxygen Sensor 13552

Bosch 13552 is a specific-fit, narrow-band heated oxygen sensor for downstream left applications on select Audi and Volkswagen models. It provides air-fuel-ratio feedback to the ECU for stable closed-loop control and emissions monitoring.

Key Features

• Actual OE Oxygen Sensor from Bosch
• Narrow-band heated oxygen sensor with 4-wire design
• Specific fit with threaded mounting and 18 mm thread diameter
• Oblong male connector with blade terminals
• Wiring harness included; harness length 64.4 in
• Metal housing with high-temperature-resistant construction
• Hex size: 22 mm

Product Details

Bosch Actual OE Oxygen Sensor 13552 uses Bosch’s OE development experience to deliver accurate switching-type O2 sensor readings for downstream left locations. The sensor’s heated narrow-band design helps the ECU maintain precise combustion control after warm-up, while the ceramic sensing element and optimized heater control support consistent signal response under thermal and vibration load. This Bosch oxygen sensor is a direct replacement for vehicles that require the same fit and function as the original unit, including Audi A4, Audi A4 Quattro, Audi A6, Audi A6 Quattro, and Volkswagen Passat applications listed below. This part cross-references 078906265F for the same application.

Vehicle Fitment

• Fits 1998-2000 Volkswagen Passat, Downstream Left
• Fits 1996-1999 Audi A4, Downstream Left
• Fits 1996-1999 Audi A4 Quattro, Downstream Left
• Fits 1998-1999 Audi A6, Downstream Left
• Fits 1998-1999 Audi A6 Quattro, Downstream Left
• Fits 1999 Audi A6 Quattro, Downstream Left, from chassis # 4B..W..000 001

Common Replacement Reasons

• Check engine light related to oxygen sensor performance
• Slow or inaccurate downstream O2 sensor signal
• Rough idle or unstable fuel control after warm-up
• Failed emissions inspection tied to sensor output
• Corrosion or heat damage at the original sensor connector

Installation Notes

Verify the downstream left location, connector shape, and 18 mm thread size before installation. Use the existing threaded mounting point and confirm harness routing matches the original layout on Audi A4, Audi A4 Quattro, Audi A6, Audi A6 Quattro, and Volkswagen Passat applications. Inspect the exhaust bung threads and connector condition before fitting the new sensor.

Quality Assurance

Bosch has more than five decades of OE oxygen sensor development, and this Actual OE Oxygen Sensor line is built to OE-proven standards for accurate signal delivery and durable operation in demanding exhaust conditions.