Denso 234-4026 Oxygen Sensor - Downstream, Upstream, Upstream Left or Upstream Right

Denso OE Style Oxygen Sensor 234-4026

Denso 234-4026 is a heated, specific-fit oxygen sensor built to OE-style dimensions for direct replacement on select Mitsubishi applications. It is engineered for accurate exhaust feedback, stable engine management, and a first-time fit on vehicles such as the Mitsubishi Eclipse, Galant, Montero Sport, Montero, and Diamante.

Key Features

• Heated oxygen sensor for faster operating response
• Specific-fit design for direct replacement
• 4-wire configuration with male connector
• Threaded mounting type with 0.708 in. thread diameter
• 39.37 in. wiring harness length
• OE Style construction for factory-like fit and function

OE Style Construction

Denso’s OE Style line is built to match original equipment fitment and electrical performance requirements. The sensor uses a precision-built design for direct replacement, and the aluminum oxide trap layer helps protect the ceramic element from silicone and lead contamination. That matters for long-term sensor stability, consistent fuel control, and reliable emissions system operation. This part number, 234-4026, is a direct-fit choice for drivers servicing Mitsubishi Eclipse and Galant applications where accurate oxygen sensor feedback is critical.

This part cross-references Bosch 13425 and NTK 23558 for the same application.

Vehicle Fitment

• Fits 2006-2012 Mitsubishi Eclipse, downstream; cylinder 3,4; OE Style
• Fits 2004-2012 Mitsubishi Galant, downstream; cylinder 2,3; OE Style
• Fits 1995-1999 Mitsubishi Eclipse, upstream; OE Style
• Fits 1997-1999 Mitsubishi Montero Sport, upstream; California exempt parts can be used on pollution controlled vehicles in California.; OE Style
• Fits 1994-1996 Mitsubishi Diamante, upstream right; OE Style
• Fits 1995-1996 Mitsubishi Montero, upstream left; California exempt parts can be used on pollution controlled vehicles in California.; OE Style
• Fits 1994 Mitsubishi Diamante, upstream right; Excluding California.; OE Style

Common Issues This Sensor Can Address

• Check engine light related to oxygen sensor performance
• Incorrect air-fuel mixture readings from a worn sensor
• Reduced fuel economy caused by slow sensor response
• Rough idle or drivability concerns tied to exhaust feedback errors
• Emissions test failures caused by a failing upstream or downstream sensor

Installation Notes

Confirm the connector style, wire count, thread diameter, and sensor position before installation. This is a specific-fit, threaded heated oxygen sensor with a 4-wire male connector, so matching the original location and harness routing is important. Use the vehicle’s exact year, model, and sensor position to verify compatibility before ordering.

Quality Assurance

Denso manufactures and tests this oxygen sensor to OE standards for consistent fit and performance. The OE Style design supports factory-like replacement on Mitsubishi Eclipse, Galant, Montero Sport, Montero, and Diamante applications, with attention to durability and accurate exhaust sensing.