Abstract: A method (42) is disclosed for detecting the usage of a heater (31) in a block (30) of an internal combustion engine (11). The method (42) uses temperature measurements of the engine coolant and any ambient air used to create the air/fuel mixture. Based on the difference between the temperatures, the temperatures are weighted and added to create a temperature variable. The temperature variable is used by the electronic engine control module (34) to create an air/fuel mixture which will allow the internal combustion engine (11) to start smoothly. The method (42) operates on this modified temperature; i.e., the temperature variable, which is not the temperature of the engine coolant, nor the ambient air, and allows for the stoichiometric balance of the air/fuel mixture to be modified to optimize performance of the internal combustion engine (11) during a cold start in cold weather with warm engine coolant.

Abstract: A method and system for determining and controlling the fuel mass to be delivered to an individual cylinder of an internal combustion engine during engine transients compensates for fuel transport dynamics and the actual fuel injected into the cylinder. A plurality of engine parameters are sensed, including cylinder air charge. An initial base desired fuel mass is determined based on the plurality of engine parameters. An initial transient fuel mass is also determined based on prior injection history for that cylinder. A desired injected fuel mass to be delivered to the cylinder is determined based on the initial base desired fuel mass and the initial transient fuel mass. These same calculations are then used to compensate for changes to the base desired fuel mass while the fuel injection is in progress, resulting in an updated desired injected fuel mass. Finally, the injection history for that cylinder is updated to account for the actual desired fuel mass delivered to the cylinder.

Abstract: A method and system for controlling fuel delivery to an individual cylinder of an internal combustion engine during engine cranking compensates for fuel transport dynamics and the actual fuel injected into the cylinder. A plurality of engine parameters are sensed, including engine temperature, inducted air mass per cylinder and number of engine intake events since cranking. A temperature of the engine stored at key-off is determined. A new puddle mass estimate for the cylinder is determined based on the decay ratio of the new puddle mass estimate to the prior puddle mass estimate stored before key-off utilizing the temperature of the engine stored at key-off. A desired fuel mass to be injected into the cylinder is then determined based on the new puddle mass estimate and the plurality of engine parameters.

Abstract: A managed fuel air control system is provided that transitions between a closed loop stoichiometric A/F mode and an open loop lean A/F mode of operation. When conditions permit open loop lean operation, the engine A/F is ramped from stoichiometric to the desired lean A/F. Periodically, while operating in the open loop lean mode, the system returns to the closed loop stoichiometric mode to update an open loop correction factor used during the open loop lean mode. The time at stoichiometric is usually limited to the time it takes to correct errors in calibration data that have occurred during open loop operation. During lean operation, the adaptive corrections learned at stoichiometric A/F are applied.