Bosch 15798 Oxygen Sensor - Downstream

Bosch Validated Oxygen Sensor for Downstream Use

Bosch Part Number 15798 is a specific-fit, narrow-band heated oxygen sensor built for downstream emission control applications. It delivers air-fuel-ratio feedback to the ECU to help maintain stable combustion control and reduce emissions under changing operating conditions.

The Bosch Validated Oxygen Sensor line reflects Bosch OE development experience, including ceramic sensing elements, optimized heater control, and high-temperature materials for consistent signal performance in demanding thermal and vibration environments.

Key Features

• Specific-fit oxygen sensor for direct application matching
• Narrow-band heated sensor design for closed-loop fuel control
• 4-wire configuration with blade terminals and square connector
• Threaded mounting with 18 mm thread size and 22 mm hex size
• Wiring harness included with 17.5 in harness length
• Metal housing with steel finish for underbody durability
• Bosch Part Number 15798 for catalog and cross-reference lookup

Detailed Description

This Bosch oxygen sensor is engineered for downstream monitoring on select Suzuki applications, including 2006-2008 Suzuki Grand Vitara, downstream, and 2001 Suzuki Esteem, downstream. It measures exhaust oxygen content and sends precise switching-type signals to the ECU so the engine management system can adjust fuel delivery accurately. Bosch Part Number 15798 is a practical OE-style replacement for drivers servicing emission control faults or restoring proper sensor response.

As part of the Bosch Validated Oxygen Sensor line, this sensor uses Bosch’s long-running OE sensor development background to support fast light-off, accurate lambda feedback, and reliable closed-loop operation. This part cross-references Monroe Shocks & Struts (e.g., 1821365G41, 1821366J11) for the same application.

What It Helps Address

• Check engine light related to oxygen sensor performance
• Slow or inaccurate downstream sensor readings
• Fuel control issues caused by degraded exhaust feedback
• Emission test failures tied to sensor response problems
• Rough combustion control from worn narrow-band sensor output

Installation Notes and Tips

Verify the connector shape, wire count, thread size, and downstream position before installation. This sensor uses a threaded mount with a 18 mm thread diameter and a 4-wire harness, so matching the original connector and routing is important for proper fitment. For 2006-2008 Suzuki Grand Vitara and 2001 Suzuki Esteem, confirm the downstream location and compare the original sensor connector before replacement.

Quality Assurance

Bosch has more than five decades of OE oxygen sensor development behind this Validated Oxygen Sensor line. The design uses durable materials and heater control strategies intended to maintain stable operation in high-heat, high-vibration exhaust environments.