Bosch 13847 Oxygen Sensor - Upstream

Bosch Validated Oxygen Sensor for Upstream Control

Bosch Validated Oxygen Sensor 13847 is a specific-fit, narrow-band heated O2 sensor built for upstream air-fuel monitoring. It provides the ECU with precise switching-type oxygen readings to support stable combustion control and lower emissions in normal driving conditions.

Compatible With 2004-2005 Buick Rainier, upstream; 2004-2005 Chevrolet Trailblazer and Trailblazer EXT, upstream; 2004-2005 GMC Envoy, Envoy XL, and Envoy XUV, upstream; 2004-2005 Isuzu Ascender, upstream; 2005 Saab 9-7x, upstream; and 2004 Oldsmobile Bravada, upstream.

Key Features

• Bosch Validated Oxygen Sensor line for OE-style replacement performance
• Part number 13847 for direct application lookup
• Narrow-band heated oxygen sensor with 4-wire design
• Specific fit with threaded mounting and 18 mm thread size
• Trapezoid male connector with blade terminals
• Wiring harness included for vehicle-specific installation
• Built with ceramic sensing elements and high-temperature-resistant materials
• Designed for upstream placement where air-fuel feedback is critical

Detailed Description

Bosch 13847 is a Bosch Validated Oxygen Sensor engineered for vehicles that use a narrow-band heated upstream sensor to manage fuel delivery. Bosch has decades of OE oxygen sensor development behind this design, including early thimble-style sensors and later planar narrowband technology that improves light-off speed, lambda accuracy, and closed-loop response. For drivers servicing a Buick Rainier, Chevrolet Trailblazer, GMC Envoy, or Saab 9-7x, this sensor supports accurate exhaust feedback so the engine computer can maintain proper mixture control.

This part cross-references GM 12586996 and 8125869960 for the same application.

What This Sensor Helps Address

• Check engine light related to oxygen sensor performance
• Rough idle caused by inaccurate upstream air-fuel readings
• Fuel trim issues from slow or inconsistent sensor switching
• Failed emissions inspection tied to sensor response problems
• Reduced closed-loop fuel control on affected GM and Saab applications

Installation Notes and Tips

Verify the upstream sensor location before ordering, since this part is specific to the listed applications. Confirm the 4-wire harness, trapezoid connector, 18 mm thread size, and threaded mounting style match the original sensor. Inspect the exhaust bung threads and connector condition before installation, and route the harness away from heat sources and moving components.

Quality Assurance

Bosch backs this oxygen sensor with more than five decades of OE development experience. The sensor uses durable materials, optimized heater control, and a design intended to maintain consistent performance under heat and vibration in everyday service.