Walker 250-21051 Oxygen Sensor - Upstream

Walker OE Oxygen Sensor for Toyota Upstream Applications

Walker Products OE oxygen sensor Part Number 250-21051 is a specific-fit replacement for select Toyota upstream applications. Built for the correct mounting position and ECU feedback requirements, it supports accurate air-fuel monitoring on older Toyota engines.

Key Features

• Specific-fit oxygen sensor for upstream installation
• Non-heated sensor design
• 1-wire configuration with 20-gauge wiring
• 11.34 in. wiring harness length and 14.88 in. overall length
• 18.0 mm thread diameter with flange mount design
• Female connector with radiused polygon shape
• Walker Products OE line for application-specific replacement

Detailed Description

Walker Products OE focuses on application-matched engine management sensors, and Part Number 250-21051 follows that approach with a specific-fit upstream oxygen sensor design. It is engineered for the correct vehicle position and diagnostic feedback expected by the ECU, making it a direct replacement choice for older Toyota fuel and emissions systems. This part number 250-21051 is used on select Toyota Camry, Celica, Corolla, Cressida, 4Runner, Pickup, Supra, Tercel, Van, Starlet, and Corona models in upstream locations.

Compatible With 1980-1992 Toyota upstream oxygen sensor applications, including Toyota Camry, Toyota Celica, Toyota Corolla, Toyota Cressida, Toyota 4Runner, Toyota Pickup, Toyota Supra, Toyota Tercel, Toyota Van, Toyota Starlet, and Toyota Corona. This part cross-references no listed aftermarket part numbers in the provided data.

What It Helps Address

• Check engine light related to upstream oxygen sensor faults
• Poor engine performance from incorrect air-fuel feedback
• Higher fuel consumption caused by a failing sensor
• Increased exhaust emissions from inaccurate sensor readings
• Diagnostic trouble codes stored in the ECU for sensor-related issues

Installation Notes and Tips

Verify the vehicle’s emissions configuration before ordering, since some Toyota applications listed here are for non-California or California-ESV setups only. Confirm the upstream mounting position, connector style, thread diameter, and harness length against the original sensor before installation. Inspect the sensor wiring harness and connector for damage, since physical wear can shorten service life and affect readings.

Quality Assurance

Walker Products states that its engine management and oxygen/air-fuel sensors are developed as OE replacement parts and manufactured under Automotive ISO9001/TS 16949 quality systems. Since 1946, Walker Products has supplied engine management sensors and fuel system components for vehicle applications worldwide.