Your 2022 Buick Envision should deliver smooth, refined power from its turbocharged engine. When noticeable vibration develops alongside a check engine light and code P0302, you're experiencing cylinder 2 misfire—a condition where combustion isn't occurring properly in one specific cylinder, throwing off the engine's balance.
Why Cylinder 2 Misfires Cause Vibration
A four-cylinder engine like the Envision's 2.0L turbo relies on each cylinder firing in sequence to produce smooth power. When cylinder 2 misfires, it's not contributing its share of power pulses. This imbalance creates vibration felt through the steering wheel, seats, and sometimes the entire vehicle.
What P0302 Indicates
P0302 tells you the PCM has detected misfires specifically in cylinder 2. Unlike random misfire codes (P0300), a cylinder-specific code helps narrow your investigation to components serving that cylinder or systems affecting it.
Common Causes of Cylinder 2 Misfires
Ignition System Failure
The most common culprits—the spark plug or ignition coil for cylinder 2 may have failed. Coils can fail internally while appearing normal externally, especially under load when heat stress increases.
Fuel Injector Problems
The cylinder 2 injector may be clogged, electrically failing, or leaking. Injector issues prevent proper fuel delivery for combustion.
Compression Loss
Low compression in cylinder 2 from worn rings, damaged valves, or gasket issues prevents proper combustion even with good spark and fuel.
Vacuum Leak
A vacuum leak affecting cylinder 2's intake runner creates a local lean condition causing misfires in that cylinder.
Carbon Buildup
Direct injection engines can accumulate carbon on intake valves, affecting airflow and combustion efficiency in affected cylinders.
Diagnostic Approach
- Swap test: Move the cylinder 2 coil and spark plug to cylinder 4. If the misfire follows (P0304 appears), you've found the failed component.
- Injector test: Check cylinder 2 injector resistance and operation. Compare to other injectors.
- Compression test: Test cylinder 2 compression against others. Significant difference indicates mechanical issues.
- Visual inspection: Look for obvious problems—loose connections, damaged wires, vacuum hose issues.
Repair Costs
- Spark plug replacement: $150-$300
- Ignition coil: $100-$200 each
- Fuel injector: $200-$400 each
- Carbon cleaning: $400-$700
- Compression-related repairs: $1,000-$3,000+
Continuing to Drive
Steady check engine light with mild vibration: You can drive to a service appointment. Flashing check engine light: Stop driving—active severe misfiring damages catalytic converters quickly.