Walker 350-34443 Oxygen Sensor - Downstream

Walker 350-34443 Oxygen Sensor Overview

Walker Products 350-34443 is a heated oxygen sensor built as a specific-fit OE-style replacement for downstream applications. It is engineered to provide the ECU with the feedback needed for fuel control and emissions monitoring on select Toyota Tacoma models.

Compatible With 2000-2004 Toyota Tacoma downstream oxygen sensor applications, this part number is designed around the vehicle’s mounting position, connector style, and wiring requirements for a direct-fit service replacement.

Key Features

• Heated oxygen sensor for downstream placement
• Specific fit for the intended vehicle application
• 4-wire design with 20-gauge wiring
• Male connector with radiused polygon shape
• 18.0 mm thread diameter and flange mount design
• Wiring harness length: 33.98 in.
• Overall length: 37.52 in.

Detailed Description

Walker Products Aftermarket 350-34443 is part of the Walker Products Engine Management and Oxygen/Air-Fuel sensor line, which is developed as an OE replacement for a wide range of vehicles. This sensor is intended for downstream use on select Toyota Tacoma models and is built to match the application-specific fitment position required by the vehicle’s diagnostic system. For buyers searching for a downstream oxygen sensor for 2001-2004 Toyota Tacoma or a B1S2 oxygen sensor for 2000 Toyota Tacoma California emissions applications, this part number provides a direct-fit option.

Walker Products has supplied engine management and fuel system components since 1946 and manufactures to automotive ISO 9001/TS 16949 standards. Part number 350-34443 is designed to help restore proper sensor feedback when the original unit is no longer reporting accurately to the ECU.

Vehicle Fitment

• Fits 2001-2004 Toyota Tacoma, downstream.
• Fits 2001-2004 Toyota Tacoma, downstream bank 1 sensor 2 on specific vehicle models.
• Fits 2000 Toyota Tacoma, downstream for B1S2 position in California emissions.
• Fits 2000 Toyota Tacoma, downstream for California-ESV vehicles in bank 1 position 2.

What It Helps Address

• Check engine light related to downstream oxygen sensor faults
• Poor fuel economy caused by inaccurate exhaust feedback
• Elevated exhaust emissions from a failing sensor
• Rough engine operation tied to incorrect ECU input
• Diagnostic trouble codes stored for the affected sensor circuit

Installation Notes and Tips

Before installation, inspect the sensor wiring harness and connector for heat damage, abrasion, or corrosion. Confirm the downstream mounting position, thread size, and connector style match the original part before replacement. If the vehicle has stored fault codes, verify the related circuit and clear codes after repair according to service procedures.

Quality Assurance

Walker Products manufactures engine management sensors as OE-style replacements and builds this part for the specified application and diagnostic feedback requirements. The brand operates under automotive ISO 9001/TS 16949 quality standards.