Walker 250-21007 Oxygen Sensor - Upstream

OE Oxygen Sensor for Select Hyundai, Mitsubishi, Dodge

Walker Products OE 250-21007 is a specific-fit oxygen sensor engineered as an Original Equipment replacement for select older import and domestic applications. It is designed for upstream Bank 1 Sensor 1 locations and provides the ECU with the feedback needed for proper fuel control and emissions monitoring.

Key Features

• Specific-fit oxygen sensor for the correct application and mounting position
• Non-heated sensor design with threaded mounting
• Upstream, Bank 1 Sensor 1 placement for ECU feedback
• Female connector with radiused polygon connector shape
• 28.07 in. wiring harness length and 20-gauge wire
• 18.0 mm thread diameter and 31.61 in. overall length
• Walker Products OE line for OE-style replacement coverage

Detailed Description

Walker Products OE 250-21007 is built for vehicles that require an upstream oxygen sensor in the exhaust stream to monitor air-fuel mixture and emissions performance. This part number is application-specific, so fitment is matched to the vehicle, position, and diagnostic requirements rather than being universal. It is a direct replacement choice for select Hyundai Excel, Hyundai Sonata, Hyundai Scoupe, Mitsubishi Eclipse, Mitsubishi Mirage, Mitsubishi Precis, Mitsubishi Galant, Mitsubishi Van, Dodge Colt, and Plymouth Laser applications listed below.

The Walker Products OE line focuses on replacement sensors engineered for the intended vehicle and ECU feedback strategy. For older vehicles, a failing oxygen sensor can contribute to rough running, higher fuel use, increased exhaust emissions, and a malfunction indicator light. Part number 250-21007 is intended for upstream Bank 1 Sensor 1 service where the original sensor uses a non-heated, threaded configuration.

Vehicle Fitment

• Fits 1993 Hyundai Excel, Upstream; non Calif-ESV, to 07/16/93; B1S1.
• Fits 1991-1993 Hyundai Scoupe, Upstream; non-California emissions certified; Bank 1 Sensor 1.
• Fits 1990-1993 Mitsubishi Precis, Upstream; non-California emissions certified; Bank 1 Sensor 1.
• Fits 1990-1992 Hyundai Excel, Upstream; non-California emissions certified; Bank 1 Sensor 1.
• Fits 1987-1990 Dodge Colt, Upstream; Bank 1 Sensor 1.
• Fits 1990 Hyundai Sonata, Upstream; non Calif-ESV, to 7/1/90; B1S1.
• Fits 1990 Mitsubishi Eclipse, Upstream; non-California emissions certified; Bank 1 Sensor 1.
• Fits 1987-1990 Mitsubishi Van, Upstream; Bank 1 Sensor 1.
• Fits 1990 Plymouth Laser, Upstream; non-California emissions certified; Bank 1 Sensor 1.
• Fits 1989 Hyundai Sonata, Upstream; non-California emissions certified; Bank 1 Sensor 1.
• Fits 1989 Mitsubishi Mirage, Upstream; non-California emissions certified; Bank 1 Sensor 1.
• Fits 1987-1988 Mitsubishi Mirage, Upstream; Bank 1 Sensor 1.
• Fits 1987 Hyundai Excel, Upstream; to 5/87; B1S1.
• Fits 1985-1987 Mitsubishi Galant, Upstream; Bank 1 Sensor 1.
• Fits 1987 Mitsubishi Precis, Upstream; to 5/87; B1S1.
• Fits 1986 Hyundai Excel, Upstream; Bank 1 Sensor 1.

What It Helps Address

• Rough engine operation caused by an aging upstream oxygen sensor
• Higher fuel consumption from incorrect air-fuel feedback
• Elevated exhaust emissions during closed-loop operation
• Malfunction indicator light concerns tied to oxygen sensor faults
• Diagnostic trouble codes related to Bank 1 Sensor 1 performance

Installation Notes and Tips

Confirm the vehicle’s emissions calibration before ordering, since several listed applications are for non-California emissions vehicles only. Verify the upstream location, connector style, thread diameter, and harness length against the original sensor before installation. Inspect the sensor wiring harness and connector for heat damage, abrasion, or corrosion, since damaged wiring can shorten sensor life and affect ECU feedback. This part number 250-21007 is commonly searched for Hyundai Excel, Mitsubishi Eclipse, and Dodge Colt upstream oxygen sensor replacement needs.

Quality Assurance

Walker Products OE sensors are developed as OE-style replacements for specific vehicle applications and are manufactured under Automotive ISO9001/TS 16949 certified processes. Walker Products has supplied engine management and fuel system components since 1946, with product engineering focused on application-specific fitment and diagnostic feedback requirements.