Denso 234-4041 Oxygen Sensor - Downstream or Upstream

Denso OE Style Oxygen Sensor for Mazda 626

Denso 234-4041 is an OE-style heated oxygen sensor built for specific fit applications on the Mazda 626. It is engineered for direct replacement performance with the correct connector, thread size, and harness length for the listed upstream and downstream positions.

For drivers searching for a Mazda 626 oxygen sensor replacement, this Denso part number 234-4041 is designed to match factory-style fitment and sensor response. It supports accurate exhaust feedback for the engine management system on 1998-2000 Mazda 626 applications.

Key Features

• OE Style replacement for specific-fit applications
• Heated oxygen sensor design for faster operating temperature
• 4-wire configuration with female connector
• Threaded mounting with 0.708 in. thread diameter
• 20.08 in. wiring harness length
• Built to strict OE standards for replacement fit and function
• Aluminum oxide trap layer helps protect the ceramic element from silicone and lead contamination

Detailed Product Overview

Denso 234-4041 is part of Denso’s OE Style line, which focuses on direct-fit replacement sensors built to factory specifications. The sensor is precision built for exact replacement and first-time fit, making it a practical choice when replacing a worn or slow-responding oxygen sensor on a Mazda 626. This part cross-references Bosch 13967 and NTK 22090 for the same application.

Compatible With 2000 Mazda 626, Upstream; 1998-1999 Mazda 626, Upstream; and 1998-1999 Mazda 626, Downstream. It also matches fitment notes for manifold location and OE-style replacement requirements on the listed vehicles.

Common Issues This Sensor Can Address

• Check engine light related to oxygen sensor performance
• Incorrect air-fuel feedback to the engine control system
• Reduced fuel economy caused by a degraded sensor signal
• Rough idle or hesitation tied to inaccurate exhaust readings
• Slow sensor response from age, contamination, or wear

Installation Notes and Tips

Verify the sensor position before ordering, since this part is listed for upstream and downstream locations on specific Mazda 626 applications. Confirm the connector style, wire count, and threaded mounting dimensions against the original sensor before installation. For best results, inspect the harness routing and exhaust threads during replacement to ensure proper seating and secure connection.

Quality Assurance

Denso manufactures and tests this oxygen sensor to OE standards for consistent replacement quality. The OE Style design is intended to deliver the correct part and fit for the listed Mazda 626 applications, with contamination-resistant construction that supports long-term sensor performance.