Denso 234-4518 Oxygen Sensor - Downstream Left

Denso OE Style Oxygen Sensor for Lexus IS250 and IS350

This Denso OE Style oxygen sensor is built for direct replacement on select Lexus applications, including the downstream left position on the Lexus IS250 and Lexus IS350. Part number 234-4518 is a specific-fit, heated sensor designed to match the original mounting and connector layout for a straightforward replacement.

Key Features

• OE Style replacement oxygen sensor from Denso
• Heated sensor design for faster operating response
• Specific fit for the correct application and position
• 4-wire configuration with male connector
• Threaded mounting with 0.708 in. thread diameter
• 43.31 in. wiring harness length for vehicle-specific routing

Product Details

Denso 234-4518 is engineered to OE standards for accurate replacement fitment and dependable sensor performance. It uses Denso’s aluminum oxide trap layer to help protect the ceramic sensing element from silicone and lead contamination, supporting stable engine management and efficient operation over time. This part is listed for the downstream left oxygen sensor location on 2006-2013 Lexus IS250 and 2011-2013 Lexus IS350 models, making it a direct-match choice for owners replacing a worn or failed sensor on these vehicles. This part cross-references Toyota 8946553230 for the same application.

Common Issues This Sensor May Address

• Check engine light related to oxygen sensor performance
• Incorrect air-fuel ratio readings from a degraded downstream sensor
• Reduced fuel economy caused by inaccurate exhaust feedback
• Emission test failure tied to sensor response or signal issues
• Rougher engine operation from a contaminated or aging sensor

Installation Notes and Tips

Fits 2006-2013 Lexus IS250, downstream left. Fits 2011-2013 Lexus IS350, downstream left. Confirm the connector style, wire routing, and threaded mounting location before installation. Because this is a specific-fit oxygen sensor, matching the downstream left position is important for proper installation and system operation. Part number 234-4518 should be verified against the original sensor before replacement.

Quality Assurance

Denso manufactures and tests this OE Style oxygen sensor to strict original-equipment standards for fit and function. The design focuses on accurate replacement, proper connector compatibility, and long-term resistance to contamination that can affect sensor performance.