P0263 Cylinder 1 Contribution/Balance — Causes & Fix

What Does P0263 Mean?

P0263 is a cylinder balance code. The ECU continuously monitors how much each cylinder contributes to engine speed. When cylinder 1 contributes significantly less than the others, P0263 is stored. This is almost always an injector problem — the injector is delivering too little fuel due to internal wear, carbon deposits, or a partially stuck nozzle.

P0263 at a Glance

• What it means: The ECU has detected that cylinder 1 is contributing less power than expected compared to other cylinders.
• Most common cause: Worn or failing fuel injector delivering insufficient fuel.
• Severity: Moderate — causes rough idle and reduced performance.
• Can you drive?: Yes, with caution. Performance will be reduced.
• Typical repair cost: £100-£350 for injector replacement.