Denso 234-4657 Oxygen Sensor - Downstream or Downstream Right

Denso OE Style Oxygen Sensor 234-4657

Denso 234-4657 is an OE Style heated oxygen sensor built for direct replacement on select Mitsubishi applications. It is engineered for exact fit and stable signal performance, with a threaded mounting design and a 4-wire male connector for specific-fit installation.

Compatible With 2001-2004 Mitsubishi Montero Sport downstream right, 2000 Mitsubishi Montero downstream, 1997-2000 Mitsubishi Montero Sport downstream right, and 1995 Mitsubishi Montero downstream right. This part number, 234-4657, is also a direct reference point when matching the correct downstream sensor for these vehicles.

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
• 17.32 in. wiring harness length
• OE Style construction for factory-style fit and function

OE Style Construction

Denso’s OE Style line is built to match original equipment dimensions and connection points, helping reduce fitment issues during replacement. The sensor uses an aluminum oxide trap layer to help protect the ceramic element from silicone and lead contamination, supporting consistent engine management performance and long service life. If you are sourcing a downstream oxygen sensor for a Mitsubishi Montero or Montero Sport, Denso 234-4657 provides a direct-fit option with the correct connector and mounting style.

This part cross-references Bosch (e.g., 13801, 15223) for the same application.

Common Problems This Sensor Can Address

• Check engine light related to oxygen sensor performance
• Incorrect air-fuel mixture readings from a worn downstream sensor
• Reduced fuel economy caused by inaccurate exhaust feedback
• Slow sensor response after contamination or age-related wear
• Exhaust monitoring faults on Mitsubishi Montero and Montero Sport applications

Installation Notes

• Verify downstream right or downstream position before ordering.
• Confirm connector style, wire count, and harness length against the original sensor.
• Inspect the exhaust bung threads before installation to ensure proper seating.
• Use the vehicle’s exact year and emissions configuration, especially for California-related applications noted in fitment.
• Clear diagnostic trouble codes after installation and confirm sensor operation with a scan tool.

Quality Assurance

Denso manufactures and tests this oxygen sensor to OE standards for precise replacement fitment and dependable operation. The OE Style design reflects factory-style dimensions and connection points, making 234-4657 a technical replacement choice for select Mitsubishi Montero and Montero Sport downstream applications.