Bosch 18252 Oxygen Sensor - Downstream

Product Overview

Bosch 18252 is a direct-fit, heated narrow-band oxygen sensor for downstream applications. It is built for specific fitment and uses a 4-wire, blade-terminal design with a rectangular connector for straightforward replacement on supported vehicles.

Fits 2015-2019 INFINITI QX80, downstream. Fits 2017-2019 Nissan Armada, downstream. Fits 2017-2022 Nissan Rogue Sport, downstream.

Key Features

• Direct-fit oxygen sensor for specific applications
• Heated narrow-band design for stable closed-loop operation
• 4-wire configuration with blade terminals and rectangular connector
• Threaded mounting with 18 mm thread diameter and 22 mm hex size
• Metal housing and high-temperature materials for demanding exhaust conditions

Detailed Description

Bosch Validated Oxygen Sensor 18252 is engineered to provide precise air-fuel-ratio feedback to the ECU, helping maintain stable combustion control and lower emissions. Bosch’s narrow-band sensor design uses advanced ceramic elements and optimized heater control to improve response and accuracy under changing exhaust temperatures. This part number, 18252, is a direct-fit replacement for downstream sensor locations on supported Nissan and INFINITI applications, including Nissan Rogue Sport, Nissan Armada, and INFINITI QX80.

As part of the Bosch Validated Oxygen Sensor line, this sensor reflects Bosch’s OE development background and focus on consistent signal quality. The threaded mounting style, 18 mm thread size, and 11.2-inch sealing-surface-to-connector length support a precise replacement match where the original sensor uses the same configuration. Part number 18252 is also cross-referenced to 226A0EZ30A for the same application.

Common Issues It May Address

• Fault codes related to oxygen sensor performance
• Unstable air-fuel ratio feedback to the engine control unit
• Reduced closed-loop fuel control accuracy
• Emissions-related drivability concerns from a worn downstream sensor
• Slow sensor response caused by heat cycling and vibration exposure

Installation Notes and Tips

Confirm the downstream position, connector style, thread size, and harness length before installation. This Bosch 18252 oxygen sensor uses a direct-fit, specific application design, so matching the original connector and mounting details is important for proper installation. Verify the vehicle’s original sensor configuration against the listed fitment for Nissan and INFINITI models before replacement.

Quality Assurance

Bosch draws on more than five decades of OE sensor development and supplies aftermarket oxygen sensors built to OE-proven standards. The Bosch 18252 is part of the Bosch Validated Oxygen Sensor line, which emphasizes accurate signal output and durable construction for demanding exhaust environments.