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Cranking fuel

Cranking fuel

📄️ After Start Enrichment

After-start enrichment is important because an engine that has just fired up is still stabilizing and needs extra fuel for a short period before it can idle cleanly. Even if cranking enrichment got the engine to start, the intake ports, combustion chambers, and sensors are still cold, fuel isn’t atomizing well yet, and airflow is uneven. This creates a natural tendency for the mixture to go lean right after the engine catches. After-start enrichment temporarily adds extra fuel to prevent stumbling, stalling, or surging during these first few seconds. As the engine warms slightly and airflow smooths out, the enrichment tapers off, handing control back to the base fuel table. Without after-start enrichment, engines often start but won’t stay running or will run very roughly right after ignition.