When your 2020 Chevrolet Traverse displays the P0305 code, the engine control module has detected repeated misfires in cylinder 5. The 2020 Traverse is powered exclusively by the 3.6L V6 engine producing 310 horsepower, which has cylinders numbered 1-6, making P0305 a legitimate diagnostic code.
2020 Traverse Powertrain
The second-generation 2020 Traverse uses GM's 3.6L High-Feature V6 (LFY) as its sole engine option. This naturally aspirated V6 uses variable valve timing, direct injection, and cylinder deactivation (on some variants) for improved efficiency.
Cylinder 5 Location
On GM's transversely-mounted 3.6L V6, cylinder 5 is positioned on the rear bank (toward the firewall) in the center position. Access may be challenging due to the engine's placement and surrounding components.
Common Causes
Spark plug wear is the most common cause, especially approaching the 100,000-mile service interval. Ignition coil failure can occur individually at cylinder 5. Direct injection engines are susceptible to carbon buildup on intake valves over time, affecting cylinder sealing. High-pressure fuel pump or injector issues can cause lean misfires. Vacuum leaks near the intake manifold affect individual cylinder air-fuel ratios.
Diagnostic Process
Read all diagnostic codes and freeze frame data. Access cylinder 5's spark plug on the rear bank and inspect for wear, fouling, or damage. Test the ignition coil through resistance measurement and swap testing. Check for vacuum leaks. On higher-mileage Traverses, intake valve carbon inspection may be beneficial.