O2 Oxygen Sensor Upstream Downstream for Nissan Maxima (2004-2008) 3.5L

Direct-Fit 4-Piece Oxygen Sensor Kit for 2004-2008 Nissan Maxima (A34)

What it Does: The direct-fit oxygen sensor kit replaces degraded upstream and downstream sensors on the 2004-2008 Maxima to restore accurate closed-loop air-fuel feedback, resolve diagnostic trouble codes, and recover factory fuel efficiency.

The Stock Nissan Maxima Sensor Wear & Fuel Trim Drift

With prolonged exposure to high exhaust gas temperatures and carbon contamination, the factory zirconia sensing elements and internal heater circuits inside the A34 exhaust stream inevitably foul. Sluggish sensor switching delays closed-loop correction, causing the VQ35DE engine control module to miscalculate short- and long-term fuel trims. This unmetered rich or lean running condition leads to spark plug fouling, premature catalytic converter thermal stress, increased emissions, and persistent check engine lights (such as P0420, P0430, P0171, or P0174).

The Engineering Solution

This complete 4-piece sensor package provides matched dual upstream air-fuel ratio sensors and dual downstream monitoring sensors to fully refresh both cylinder banks. Engineered with high-grade planar ceramic sensing elements housed inside dual-layer 304 stainless steel protective shields, these units resist thermal shock and soot accumulation. Factory-keyed weather-pack electrical connectors and pre-loomed heat-resistant wiring harnesses provide a plug-and-play installation without wire splicing, matching OE response curves and heater resistance tolerances.

What's Included

• 2x Upstream Oxygen Sensors
• 2x Downstream Oxygen Sensors

Technical Specifications

Compatibility

• 2004-2008 Nissan Maxima SE Sedan 4-Door 3.5L V6
• 2004-2008 Nissan Maxima SL Sedan 4-Door 3.5L V6

Frequently Asked Questions & Fitment Warnings

Does this fit the A34 Maxima?

Yes, this is a direct fit for the 2004-2008 Nissan Maxima equipped with the VQ35DE 3.5L V6 engine across all factory trim configurations.

Should I replace all four O2 sensors at the same time?

Yes, replacing both upstream and downstream sensors together prevents mismatched cross-bank signal delay and ensures proper catalyst efficiency monitoring by the ECM.

The Nissan VQ Caliber

Maintain the high-revving output, sharp throttle delivery, and refined powerband that define Nissan's legendary VQ-series V6 powertrain with matched closed-loop exhaust feedback components.