Denso 234-4255 Oxygen Sensor - Downstream

Denso 234-4255 Oxygen Sensor Overview

Denso 234-4255 is an OE Style heated oxygen sensor built for specific downstream applications on select Chevrolet, Pontiac, and Saturn vehicles. It is precision built for a first-time fit and engineered to support accurate exhaust monitoring, stable engine performance, and efficient fuel control.

Compatible With 2008-2010 Chevrolet Malibu, downstream; 2008-2010 Pontiac G6, downstream; and 2008-2010 Saturn Vue, downstream. This Denso oxygen sensor is also a direct replacement for other listed OE-style downstream applications across the same platform family.

Key Features

• OE Style replacement for specific downstream sensor locations
• Heated oxygen sensor design for faster operating response
• 4-wire configuration with female connector
• Threaded mounting type with 0.708 in. thread diameter
• Wiring harness length: 14.76 in.
• Precision-built for exact replacement and proper fit
• Aluminum oxide trap layer helps protect the ceramic element from silicone and lead contamination

Product Details

Denso 234-4255 is part of Denso’s OE Style line, which focuses on direct-fit replacement sensors built to match factory specifications. The sensor is manufactured and tested to OE standards, with attention to connector style, thread size, harness length, and mounting design for straightforward installation on the correct downstream location. For drivers servicing a Chevrolet Malibu, Pontiac G6, or Saturn Vue, this part number provides a direct replacement path that supports emissions system performance and fuel management accuracy.

This part cross-references Bosch 18079 and NTK 21568 for the same application.

What It Helps Address

• Check engine light caused by a failing downstream oxygen sensor
• Incorrect exhaust oxygen readings affecting fuel trim control
• Reduced fuel efficiency from an aging or contaminated sensor
• Emissions test failures related to sensor response issues
• Rougher engine operation tied to inaccurate exhaust feedback

Installation Notes

Verify the downstream position, connector style, wire count, and thread diameter before installation. Compare the original sensor harness length and mounting style to confirm direct replacement on the intended vehicle. For best results, inspect the exhaust threads and connector terminals before installing the new sensor.

Quality Assurance

Denso manufactures this oxygen sensor to strict OE standards and tests it for exact replacement fitment. The design includes an aluminum oxide trap layer to help protect the sensing element from silicone and lead contamination, supporting long-term sensor performance.