Denso 234-5120 Air / Fuel Ratio Sensor - Upstream, Upstream Left or Upstream Right

Reliable Air/Fuel Ratio Sensor for Audi Vehicles

The Denso OE Style 234-5120 air/fuel ratio sensor is designed specifically for select Audi models, including the A4, A4 Quattro, A5 Quattro, A6, A6 Quattro, and Q5. This heated sensor ensures accurate emissions control and optimal engine performance by precisely monitoring the air-to-fuel mixture.

• Heated sensor type for faster response times
• Specific fit for Audi A4, A4 Quattro, A5 Quattro, A6, A6 Quattro, and Q5
• 22.56-inch wiring harness length for proper installation
• Five-wire configuration with male connector
• Thread diameter of 0.711 inches for secure mounting
• Regular grade type for standard OEM replacement

About the Denso OE Style Product Line

The OE Style line from Denso offers direct replacement parts engineered to meet original equipment specifications. The 234-5120 air/fuel ratio sensor maintains the quality and fitment standards expected from factory components, ensuring compatibility and reliable operation within the emission control system of your Audi vehicle.

Detailed Product Description

This air/fuel ratio sensor features a heated element that allows it to reach operating temperature quickly, improving sensor accuracy and reducing emissions during cold starts. The 22.56-inch wiring harness length provides sufficient reach for proper connection without excess slack. With five wires and a male connector, this sensor integrates seamlessly with the vehicle’s existing wiring harness. The 0.711-inch thread diameter ensures a secure and precise fit in the exhaust system. Designed specifically for Audi models such as the A4, A4 Quattro, A5 Quattro, A6, A6 Quattro, and Q5, this sensor supports the vehicle’s emission control system by delivering accurate air/fuel mixture data to the engine control unit.

Common Issues Addressed by This Sensor

• Incorrect air/fuel mixture readings causing poor fuel economy
• Check engine light triggered by faulty sensor signals
• Increased emissions due to sensor malfunction
• Engine performance problems related to improper fuel mixture
• Failed emissions tests linked to sensor degradation

Installation Notes and Tips

Ensure the vehicle is cool before installation to avoid burns. Disconnect the battery prior to sensor replacement to prevent electrical shorts. Use the correct tools to remove the old sensor and install the new one with the specified 0.711-inch thread diameter. Verify the wiring harness length of 22.56 inches is sufficient for your vehicle’s routing. Confirm the male connector securely mates with the vehicle’s wiring harness. After installation, clear any diagnostic trouble codes and perform a test drive to verify proper sensor operation.

Quality Assurance and Warranty

The Denso OE Style 234-5120 air/fuel ratio sensor is manufactured to meet OEM standards for fit, form, and function. While specific warranty details may vary, Denso products typically come with a limited warranty covering defects in materials and workmanship. This ensures dependable performance and peace of mind when replacing emission control sensors on your Audi A4, A4 Quattro, A5 Quattro, A6, A6 Quattro, or Q5.