Bosch 13900 Oxygen Sensor - Downstream or Upstream

Bosch Oxygen Sensor for OE-Style Emissions Control

Bosch Part Number 13900 is a narrow-band heated oxygen sensor built for precise air-fuel ratio feedback to the ECU. It supports stable combustion control and emissions management for specific Toyota and Jaguar applications, including the Toyota MR2 Spyder and Jaguar XJ12/XJS.

Key Features

• Bosch Engineered Oxygen Sensor line with OE development heritage
• Narrow-band heated O2 sensor for faster closed-loop operation
• Specific fit design with a threaded 18 mm mounting style
• 4-wire configuration with blade terminals and rectangular connector
• Metal housing and high-temperature-resistant construction for demanding exhaust conditions
• Wiring harness included; harness length measures 31.3 in
• Overall length measures 34.6 in with a 22 mm hex size

Product Details

Bosch 13900 uses a switching-type narrow-band design to report exhaust oxygen content to the engine control unit, helping the system maintain the correct air-fuel balance. Bosch developed this sensor family from its long-running OE oxygen sensor technology, including later planar narrowband designs that improve light-off speed, lambda accuracy, and closed-loop response. This part cross-references 8946517201 and LNA1682AC for the same application.

Vehicle Fitment

• Fits 2000-2005 Toyota MR2 Spyder, Downstream
• Fits 1995-1996 Jaguar XJ12, Upstream
• Fits 1995 Jaguar XJS, Upstream

Common Issues This Sensor Can Address

• Fault codes related to oxygen sensor response or signal range
• Unstable air-fuel ratio feedback during closed-loop operation
• Increased exhaust emissions from a worn upstream or downstream sensor
• Rough idle or drivability concerns tied to inaccurate O2 readings
• Delayed sensor switching caused by age, heat, or contamination

Installation Notes

Verify the sensor position before installation: this part is listed for downstream use on the Toyota MR2 Spyder and upstream use on the Jaguar XJ12 and Jaguar XJS. Confirm the 18 mm thread size, 4-wire connector layout, and harness routing before removal of the original sensor. Use proper exhaust sensor tools and inspect the connector and wiring path for heat damage or corrosion during replacement.

Quality Assurance

Bosch backs this oxygen sensor with more than five decades of OE development experience, and the design reflects the same engineering approach used for original equipment applications. The sensor uses durable ceramic elements, controlled heating, and heat-resistant materials to maintain consistent operation under thermal and vibration load.