O2 Oxygen Sensor Upstream For Nissan Vehicles (2004-2009)

Precision Air-Fuel Monitoring for Nissan VK56DE, VQ35DE, and VQ40DE Platforms

Who It’s For: Engineered for Nissan owners running the legendary VQ and VK series powerplants who are seeing a dip in fuel economy or a sluggish hesitation during mid-range acceleration. Whether you are towing with the VK56DE or carving corners in a VQ35DE-equipped 350Z, these sensors are critical for maintaining peak combustion efficiency.

The Symptom: The factory upstream oxygen sensors on Nissan’s high-displacement V6 and V8 engines are the "eyes" of the ECU. Over time, heat cycles and carbon buildup contaminate the sensor element, leading to "lazy" signal response. This causes the engine to run in a sub-optimal fuel map, often resulting in a rich condition that fouls spark plugs, kills your miles-per-gallon, and makes the throttle feel like it’s moving through mud when you try to merge into traffic.

The Engineering Fix: These premium upstream sensors utilize a sophisticated 5-wire configuration designed to provide real-time wideband-style feedback to the ECM. By accurately measuring the oxygen content in the exhaust stream before it hits the catalytic converter, the system allows for instantaneous fuel trim adjustments. This ensures the stoichiometric ratio is maintained, restoring that crisp throttle snap and ensuring the engine isn’t fighting against its own timing maps.

Why Mechanics Choose This Kit

• Restored Volumetric Efficiency: By providing accurate data to the ECU, these sensors help the VK and VQ engines optimize their variable valve timing (VTC) for better torque delivery.
• OEM-Spec Integration: Featuring a 540mm lead and the correct factory-style connector, this is a true "Plug-and-Play" solution with no wire hacking required, preserving the integrity of your engine harness.
• Laboratory Tested: Built to strict quality control standards to withstand the high EGTs (Exhaust Gas Temperatures) common in Nissan’s performance-tuned 3.5L and 4.0L manifolds.

Technical Specifications

Compatibility & OEM Reference

Fits the Following Vehicles:

• 2004-2006 Nissan Titan 5.6L V8
• 2004-2009 Nissan Quest 3.5L V6
• 2004-2007 Nissan Murano 3.5L V6
• 2004-2008 Nissan Maxima 3.5L V6
• 2005-2006 Nissan X-Terra 4.0L V6
• 2005 Nissan Pathfinder 4.0L V6
• 2005-2006 Nissan Frontier 4.0L V6
• 2005-2006 Nissan Armada 5.6L V8
• 2005-2006 Nissan 350Z 3.5L V6

Interchange Part Numbers:

12499877

The Performance Promise

Buy with confidence. Don’t let a tired sensor bottleneck your Nissan’s performance. We provide high-quality components designed to meet or exceed factory output. Backed by real automotive experts and fast shipping.