Inventors:
Michael J Prucka - Grass Lake MI, US
Gregory L Ohl - Ann Arbor MI, US
Zhong Li - Westland MI, US
Mark J Duty - Goodrich MI, US
Eugenio DiValentin - Brighton MI, US
Michael A Bonne - Leonard MI, US
Assignee:
DaimlerChrysler Corporation - Auburn Hills MI
International Classification:
F02D 13/04
Abstract:
A method for controlling airflow in an intake manifold of a multiple-displacement engine during an engine displacement mode transition includes determining, before a displacement mode transition, a post-transition mass air flow rate necessary to maintain a pre-transition engine torque output, as well as an airflow transient multiplier based on engine speed and an estimated post-transition manifold air pressure. After multiplying the requested mass air flow rate with the transient multiplier, the resulting compensated requested mass air flow rate is divided by a maximum mass air flow rate to obtain a requested percent airflow. The percent airflow is thereafter used with engine speed to determine a requested post-transition manifold air pressure-to-barometric pressure ratio, for example, using a lookup table; and the requested post-transition pressure ratio is used to determine a transient post-transition throttle position, to which an engine throttle will be moved upon initiating the displacement mode transition.