Methods and systems for pre-ignition control in a variable displacement engine

摘要

Methods and systems are provided for reducing pre-ignition incidence in a variable displacement engine during reactivation from a VDE mode. During conditions when one or more deactivated cylinders are reactivated to elevated engine loads, the reactivated cylinder(s) may be temporarily and preemptively enriched to reduce the possibility of cylinder pre-ignition. The preemptive enrichment is learned and further adjusted in a closed loop fashion.

主权项

1. A method for an engine, comprising:
while reactivating a cylinder responsive to a higher than threshold torque demand, and before an indication of pre-ignition in the cylinder is received, enriching the reactivated cylinder, the enrichment adjusted based on each of the torque demand and a preceding duration of cylinder deactivation.