Bosch 15586 Oxygen Sensor - Upstream

Bosch Wideband A/F Sensor for Subaru and Saab

Bosch Validated Oxygen Sensor 15586 is a specific-fit wideband air-fuel sensor built for upstream applications on select Subaru and Saab vehicles. It provides the ECU with continuous air-fuel ratio data across the full lambda range, helping maintain precise mixture control in changing load and temperature conditions.

For drivers searching for a Subaru Impreza upstream oxygen sensor, Subaru Forester upstream O2 sensor, or Bosch 15586 replacement for Legacy and Outback applications, this Bosch sensor matches the OE-style configuration used on the listed vehicles.

Key Features

• Wideband A/F oxygen sensor for continuous air-fuel ratio measurement
• Specific fit design with 4-wire, heated construction
• Threaded mounting with 18 mm thread diameter and 22 mm hex size
• Square female connector with included wiring harness
• Overall length: 23.2 in; sealing surface to connector end: 22 in
• Steel finish with metal housing for standard replacement use
• Bosch Validated Oxygen Sensor line for OE-style aftermarket coverage

Product Details

Bosch 15586 is a wide band oxygen sensor engineered for upstream placement on select Subaru Impreza, Forester, Legacy, Outback, and Saab 9-2X models. Unlike a traditional switching sensor, this wideband design delivers more detailed feedback to the engine control unit, supporting accurate fuel control under steady cruise, acceleration, and thermal cycling. Bosch’s Validated Oxygen Sensor line focuses on OE-proven fit and function for vehicles that rely on precise air-fuel management.

This part cross-references 22641AA13B and 22641AA33A for the same application.

What It Helps Address

• Check engine light related to upstream oxygen sensor performance
• Incorrect air-fuel ratio readings from a worn wideband sensor
• Rough idle or drivability issues tied to mixture control faults
• Reduced fuel economy caused by inaccurate sensor feedback
• Emission test failures linked to sensor response problems

Installation Notes

Fits 2005-2011 Subaru Impreza, Upstream; 2004-2010 Subaru Forester, Upstream; 2006-2009 Subaru Legacy, Upstream; 2006-2009 Subaru Outback, Upstream; 2005-2006 Saab 9-2X, Upstream. Confirm connector shape, thread size, and harness routing against the original sensor before installation. Use the vehicle’s existing mounting point and verify the upstream location on the exhaust system before replacement.

Quality Assurance

Bosch has more than five decades of OE development in oxygen sensor technology, and this sensor reflects that experience with a robust ceramic design, fast light-off behavior, and controlled heater operation for stable performance in demanding conditions.