Denso 234-4666 Oxygen Sensor - Downstream or Upstream

Denso OE Style Oxygen Sensor 234-4666

Denso 234-4666 is an OE Style heated oxygen sensor built for specific-fit replacement in select Volkswagen and Audi applications. It is engineered for accurate exhaust feedback, stable engine management, and a first-time fit on the listed upstream and downstream positions.

Key Features

• Heated oxygen sensor with specific fit for direct replacement
• OE Style design for factory-like fitment and connector alignment
• 4-wire configuration with male connector
• Threaded mounting type with 0.708 in. thread diameter
• 52.36 in. wiring harness length for listed vehicle applications
• Built to strict OE standards with precision-built components
• Aluminum oxide trap layer helps protect the ceramic element from silicone and lead contamination

Detailed Description

This Denso oxygen sensor is designed for drivers servicing emissions and fuel-control systems on Volkswagen Passat, Golf, Jetta, Cabrio, EuroVan, and Audi A4/A4 Quattro applications. The Denso OE Style line focuses on exact replacement dimensions and connector design, helping restore proper exhaust oxygen monitoring on vehicles that rely on precise sensor input for air-fuel control. Part number 234-4666 is a direct-fit replacement for the listed upstream and downstream positions, depending on application.

Denso manufactures and tests these sensors to OE standards, and the sensor construction includes an aluminum oxide trap layer that helps shield the ceramic element from contamination. This supports consistent sensor response and long service life in demanding exhaust environments. This part cross-references Bosch (e.g., 13740, 15026) for the same application.

Vehicle Fitment

• Fits 1998-2001 Volkswagen Passat, Upstream
• Fits 1994 Volkswagen Passat, Upstream
• Fits 1997-2000 Audi A4 Quattro, Upstream
• Fits 1999-2000 Volkswagen EuroVan, Downstream
• Fits 1997 Volkswagen EuroVan, Downstream
• Fits 1997-1999 Audi A4, Upstream
• Fits 1996-1999 Volkswagen Cabrio, Downstream
• Fits 1997-1999 Volkswagen Golf, Downstream, USA Model
• Fits 1997-1999 Volkswagen Golf, Downstream, From Chassis #1H-W-000 001
• Fits 1997-1999 Volkswagen Jetta, Downstream
• Fits 1997-1999 Volkswagen Jetta, Downstream, USA Model
• Fits 1997-1999 Volkswagen Jetta, Downstream, From Chassis #1H-W-000 001
• Fits 1996-1998 Volkswagen Golf, Downstream
• Fits 1996-1997 Volkswagen Passat, Downstream
• Fits 1996 Volkswagen Golf, Downstream, From Chassis #1H-T-000 001
• Fits 1996 Volkswagen Jetta, Downstream, From Chassis #1H-T-000 001
• Fits 1996 Volkswagen Jetta, Downstream, USA Model, From Chassis #1H-T-000 001
• Fits 1995 Volkswagen Passat, Downstream, From Chassis #3A-S-086-001

Common Problems This Sensor Can Address

• Fault codes related to oxygen sensor performance
• Rough idle or inconsistent fuel mixture control
• Reduced fuel economy caused by inaccurate exhaust readings
• Failed emissions inspection due to a worn sensor
• Delayed or unstable engine management feedback

Installation Notes and Tips

Confirm the vehicle’s year, make, model, and sensor position before ordering, since this part is application-specific. Match the connector style, wire count, and threaded mounting dimensions to the original sensor, and verify chassis notes where listed for Golf, Jetta, and Passat applications. For best results, inspect the exhaust bung threads and wiring routing before installation.

Quality Assurance

Denso builds this OE Style oxygen sensor to strict original-equipment standards and tests each design for fit and performance consistency. The precision-built construction is intended to deliver the correct replacement part for the listed Volkswagen and Audi applications, including Denso 234-4666.