A-Premium APOS0526 Upstream O2 Oxygen Sensor 5-Wire Air-Fuel Ratio

The A-Premium APOS0526 is a direct-fit upstream O2 oxygen sensor (Bank 1, Sensor 1) engineered as a precision aftermarket replacement for select Mitsubishi vehicles equipped with 2.0L and 2.4L L4 engines. This 5-wire air-fuel ratio sensor is designed to restore proper exhaust monitoring and engine management performance.

The oxygen sensor continuously measures unburned oxygen levels in the exhaust stream and sends real-time feedback to the engine control unit (ECU), enabling the proper air-fuel mixture for optimal combustion. A failed or degraded O2 sensor can result in poor fuel economy, rough idling, reduced engine performance, and an illuminated check engine light.

Key Features:

• Direct-fit replacement — engineered to match OEM specifications with no modifications required
• 5-wire connector — plug-and-play installation for the upstream (Bank 1, Sensor 1) position
• High-grade materials — built to resist heat, moisture, and corrosion for long-term durability
• Superior sensor sensitivity — delivers accurate, responsive readings for consistent engine performance
• Rigorously tested — evaluated for fast response times and extended service life
• 3-year unlimited mileage warranty — backed by A-Premium's quality guarantee

OEM Cross-Reference Part Numbers: 1588A228, 25025083, 2345051 (234-5051), 24399

This sensor ships as a single unit and is intended for the upstream (front/pre-cat) installation position. Note: This part does not fit vehicles with California emissions specifications on certain model years.