Cylinder 1 Contribution/Balance Fault
Cylinder 1 is not producing the same power or combustion as the other cylinders, like one worker in a team doing less work than the others. The engine computer detected this imbalance and is alerting you to unequal cylinder performance.
The ECU monitors cylinder contributions through fuel injector pulse width, ignition timing, and oxygen sensor feedback to ensure each cylinder fires and combusts fuel equally. It compares cylinder 1 output to other cylinders and flags a fault when the power contribution falls outside expected parameters.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Cylinder 1 Fuel Trim | -10% to +10% | Beyond ±15% deviation from baseline |
| Cylinder 1 Combustion Efficiency | Within 5% of other cylinders | More than 5% lower than average |
Code P0264 is a moderate fault. You can generally drive to a workshop, but avoid long trips or high-load driving (motorway, uphill towing) until it is diagnosed. If the code keeps returning after clearing, or if you notice the symptoms listed above worsening, do not delay professional diagnosis. Many moderate codes have multiple possible root causes — a mechanic with live OBD data can identify the exact fault more efficiently than part-by-part trial and error.
Once the fault is repaired, P0264 can be cleared using any OBD-II scanner. Connect the scanner, navigate to "Clear Codes" or "Erase DTCs," and confirm. The check engine light turns off immediately.
The code will return if the root cause was not actually fixed. The ECM re-detects the fault within 1–3 drive cycles and sets the code again.