Walker 250-25193 Oxygen Sensor - Upstream

Walker OE Base Oxygen Sensor 250-25193

Walker OE Base Sensor 250-25193 is a specific-fit, heated wide-band oxygen sensor built for direct replacement in select Audi applications. It provides ECU feedback for air-fuel control and emissions monitoring, helping maintain proper engine management on vehicles such as the Audi Q5, Audi A6 Quattro, and Audi Q7.

Key Features

• Heated wide-band oxygen sensor for precise exhaust feedback
• Specific-fit design for the listed Audi upstream applications
• 5-wire sensor with 6-terminal configuration
• Female connector with oblong shape
• M18 x 1.5 thread size and 22 mm wrench size
• OE Base Sensor line from Walker Products

OE Base Sensor Line Details

Walker’s OE Base Sensor line focuses on application-specific engine management sensors built to match the required fitment position and diagnostic feedback expected by the ECU. Part number 250-25193 is engineered for upstream placement on the listed Audi models, including 2023-2026 Audi Q7, 2024-2025 Audi A4 allroad, 2024-2025 Audi A4 Quattro, 2024-2025 Audi A5 Sportback, 2021-2025 Audi A6 Quattro, 2024-2025 Audi Q5, 2024-2025 Audi Q5 Sportback, and 2024 Audi A5 Quattro. This part number, 250-25193, is also listed for 2021 Audi Q5 and 2021 Audi Q5 Sportback with a 6-pin connector note.

What This Sensor Helps Address

• Check engine light related to oxygen sensor performance
• Poor fuel economy caused by incorrect air-fuel feedback
• Rough engine operation from inaccurate exhaust readings
• Elevated exhaust emissions from a failing upstream sensor
• Stored ECU fault codes tied to the affected sensor circuit

Installation Notes

Confirm the connector style, wire count, and upstream location before installation. Inspect the sensor wiring harness and connector for physical damage, since damaged wiring can shorten sensor life and affect operation. Verify thread size and wrench access during replacement, and compare the original sensor configuration to the vehicle listing for the exact model year.

Quality Assurance

Walker Products manufactures engine management and oxygen/air-fuel sensors as OE-style replacement parts for global vehicle applications. The company is ISO 9001/TS 16949 certified and has produced engine management components since 1946.