When your 2020 Nissan Maxima displays the P0305 code, the engine control module has detected repeated misfires in cylinder 5. The 2020 Maxima uses the 3.5L VQ35DE V6 producing 300 horsepower. With six cylinders numbered 1-6, P0305 is a legitimate diagnostic code.
2020 Maxima Powertrain
The eighth-generation Maxima uses Nissan's proven VQ35DE 3.5L V6 engine, a naturally aspirated powerplant known for its smooth power delivery. Paired with a CVT transmission, this setup provides spirited performance for Nissan's flagship sedan.
Cylinder 5 Location
On the VQ35 V6, cylinder 5 is located on the rear bank (toward the firewall) in the center position. The transverse engine mounting makes this cylinder challenging to access, potentially requiring removal of the intake manifold or working from underneath.
Common Causes
Spark plug wear is a common cause, especially if approaching 100,000 miles. Ignition coil failure can occur at cylinder 5. The VQ35 is generally reliable but can develop intake manifold gasket issues affecting individual cylinder performance. Fuel injector problems can cause lean misfires.
Diagnostic Process
Read all codes and freeze frame data. Access cylinder 5's spark plug and inspect for wear or fouling. Test the ignition coil through resistance measurement and swap testing. Check for vacuum leaks around the intake manifold. Verify fuel injector operation.