Engine control method for reducing emissions during cold start and idling for vehicle
AssigneeHyundai Motor Company
InventorMyung-Sik Choi
Life of this patent
Estimating the term…
Abstract
An engine control method for reducing emissions during cold start and idling is provided, which includes: opening an ISA with a predetermined opening rate such that an air/fuel ratio becomes higher than a stoichiometric air/fuel ratio, and minimizing an engine load caused by an automatic transmission; performing air/fuel ratio control and ignition timing control based on engine speed and engine load, and controlling an amount of fuel injected in consideration of a quantity of wetting fuel; and determining an air flow rate according to an engine speed and coolant temperature, and performing air/fuel ratio control and ignition timing control to control an engine speed fluctuation.
Claims19
An engine control method for reducing hydrocarbon emissions during cold start and idling, the method comprising:
- opening an ISA to a predetermined open position rate such that an air/fuel ratio becomes higher than a stoichiometric air/fuel ratio;
- minimizing an engine load caused by an automatic transmission;
- initially controlling air/fuel ratio and ignition timing based on engine speed and engine load;
- controlling an amount of injected fuel based on a calculated wetting fuel value;
- determining an air flow rate according to engine speed and coolant temperature;
- and
- controlling air/fuel ratio and ignition timing to control engine speed fluctuation.
An engine control method for reducing hydrocarbon emissions during cold start and idling, the method comprising:
- (a) fully opening an ISA, and minimizing an engine load caused by an automatic transmission by controlling a line pressure of the automatic transmission such that it is not generated;
- (b) setting an air/fuel ratio as a value higher than a stoichiometric air/fuel ratio, performing ignition timing control, and controlling an amount of fuel injected based on a wetting fuel value that is determined in consideration of a number of power strokes in a specific cylinder and a total number of power strokes of a specific engine;
- (c) calculating an air flow rate based on an engine speed and a coolant temperature, and simultaneously fully opening the ISA, and performing air/fuel ratio control and ignition timing control based on engine speed and engine load;
- (d) determining if the engine speed is equal to a predetermined idle speed;
- (e) determining if a shift range is a neutral range or a parking range, if it is determined that the engine speed is not equal to the predetermined idle speed;
- (f) determining if an elapsed time from the moment when an ignition switch is turned on is less than a predetermined time, if the shift range is the neutral range or the parking range;
- (g) fully opening the ISA if it is determined that the elapsed time from the moment the ignition switch is turned on is less than the predetermined time;
- (h) determining if a change in engine speed is greater than a predetermined critical speed change;
- and
- (i) controlling an engine speed fluctuation according to air/fuel ratio control and ignition timing control if the change in engine speed is greater than the predetermined critical speed change, and controlling the engine speed fluctuation according to ignition timing control if the change in engine speed is not greater than the predetermined critical speed change.
Dependencies are inferred from the claim text.