Patent ID: 6378484
Filing Date: 2002-04-30
Classification: F01L,F02B,F02D,Y02T

Abstract:
A method for controlling a direct injection stratified charge engine having an electronically controlled throttle and controllable valve timing during transitions between a current operating mode and a desired operating mode corresponding to stratified and homogeneous operating modes to reduce variations in engine torque from a desired engine torque, the method comprising:moving the throttle to a position associated with the desired operating mode; adjusting fuel flow to substantially maintain the desired engine torque as air/fuel ratio approaches an air/fuel ratio gap between acceptable air/fuel ratios for the current operating mode and acceptable air/fuel ratios for the desired operating mode; and changing valve timing to valve timing associated with the desired operating mode to modify cylinder air charge while changing fuel injection timing associated with the current operating mode to fuel injection timing associated with the desired operating mode as the air/fuel ratio traverses the gap.