A P0303 code in your 2020 Nissan Maxima indicates the engine control module has detected persistent misfires at cylinder 3. Nissan's flagship sedan uses the powerful 3.5L VQ35DE V6 engine producing 300 horsepower. This performance-oriented powertrain demands precise cylinder operation for its smooth, refined character.
Cylinder 3 in the 3.5L V6
The VQ35DE V6 positions cylinder 3 at the rear of the front bank (radiator side). This V6 layout numbers cylinders 1-3 on one bank and 4-6 on the other. The front bank location provides relatively good access for ignition component service.
Performance Sedan Characteristics
The Maxima is positioned as a "4-Door Sports Car" with a high-revving V6 that rewards enthusiastic driving. This performance focus means the engine operates under greater stress during spirited driving, potentially accelerating wear on ignition components.
Common P0303 Causes at Four to Five Years
At this age, wear-related issues become more prevalent. Spark plug degradation affects ignition quality, especially with performance driving. Ignition coil failures occur from heat cycling. Carbon buildup on intake valves (from optional direct injection variants) restricts airflow. Fuel injector deposits affect spray patterns.
VQ35 Engine Heritage
The VQ35 engine family has won numerous industry awards and is known for reliability. Proper maintenance, especially timely spark plug replacement, ensures continued smooth operation.