What term describes the rate at which the PCM decreases the signal for additional fuel during open-loop startup?

What term describes the rate at which the PCM decreases the signal for additional fuel during open-loop startup?

• A. Minimum Temperature
• B. Engine Coolant Temperature
• C. Afterstart Enrichment
• D. Afterstart Decay

Answer: (D)

During startup, the PCM temporarily boosts fuel—that extra fueling is provided to help ignition when the engine is cold. In open-loop startup, there’s no feedback to fine-tune this mix, so the enrichment is gradually reduced as the engine warms. The rate at which this extra fuel signal decreases back toward normal fueling is called afterstart decay. That’s why this term best describes the requested concept. The other options describe sensor readings or the enrichment itself, not the rate at which the enrichment decays.

During startup, the PCM temporarily boosts fuel—that extra fueling is provided to help ignition when the engine is cold. In open-loop startup, there’s no feedback to fine-tune this mix, so the enrichment is gradually reduced as the engine warms. The rate at which this extra fuel signal decreases back toward normal fueling is called afterstart decay. That’s why this term best describes the requested concept. The other options describe sensor readings or the enrichment itself, not the rate at which the enrichment decays.