Abstract: A control method can be used for securing continuously variable valve duration (CVVD) startability when a CVVD error is recognized by a CVVD controller during an operation of a CVVD system. The control method includes performing engine startability securing control for solving the CVVD error by applying a starting air volume to starting of an engine through at least one of a valve position fixing value, a valve position threshold, or an immediately previous valve position value.

Abstract: A method of diagnosing a temperature sensor provided at a rear stage of an air filter includes: comparing a heating condition factor with a factor threshold; when the heating condition factor is less than the factor threshold, calculating a deviation between a temperature of an intake manifold and a temperature of intake air at a rear stage of an air filter; comparing a temperature threshold with the deviation; and, when the deviation exceeds the temperature threshold, diagnosing the intake air temperature sensor provided at the rear stage of the air filter as failing. According to the method, failure of a temperature sensor provided at a rear state of an air filter of an engine room can be diagnosed.

Abstract: A method of diagnosing a temperature sensor provided at a rear stage of an air filter includes: comparing a heating condition factor with a factor threshold; when the heating condition factor is less than the factor threshold, calculating a deviation between a temperature of an intake manifold and a temperature of intake air at a rear stage of an air filter; comparing a temperature threshold with the deviation; and, when the deviation exceeds the temperature threshold, diagnosing the intake air temperature sensor provided at the rear stage of the air filter as failing. According to the method, failure of a temperature sensor provided at a rear state of an air filter of an engine room can be diagnosed.

Abstract: An air-fuel ratio control method reflecting a brake booster inflow flow rate includes: determining a deviation between an actually measured pressure of an intake manifold and a model pressure of the intake manifold is equal to or greater than a predetermined value; determining that the deviation is caused by a brake operation; correcting an intake air amount by reflecting a flow rate flowing into the intake manifold from a brake booster; and performing an air-fuel ratio control based on the corrected intake air amount.

Abstract: A control method can be used for securing continuously variable valve duration (CVVD) startability when a CVVD error is recognized by a CVVD controller during an operation of a CVVD system. The control method includes performing engine startability securing control for solving the CVVD error by applying a starting air volume to starting of an engine through at least one of a valve position fixing value, a valve position threshold, or an immediately previous valve position value.

Abstract: A method for an alternate control of a continuously variable valve duration (CVVD) malfunction may include a CVVD failsafe control to resolve a calculation error of a cylinder charge amount due to a hardware failure of a CVVD system with the cylinder charge amount determined by any one of flow rate alternate, flow rate deviation correction, and valve duration update if the hardware failure is recognized by a CVVD controller, and to apply the cylinder charge amount to secure an air amount for a combustion chamber.

Abstract: A method for avoiding a measurement error of an air flow sensor for a vehicle includes an engine control unit (ECU) which predicts, in advance, occurrence of the contamination by foreign materials included in the air or condensation of moisture on a sensor measurement plate of the air flow sensor, and performs an operation for preventing the contamination by foreign materials or the condensation of moisture when the occurrence is predicted, to avoid the measurement error of the air flow sensor due to the contamination by foreign materials or the condensation of moisture on the sensor measurement plate.

Abstract: An air-fuel ratio control method reflecting a brake booster inflow flow rate includes: determining a deviation between an actually measured pressure of an intake manifold and a model pressure of the intake manifold is equal to or greater than a predetermined value; determining that the deviation is caused by a brake operation; correcting an intake air amount by reflecting a flow rate flowing into the intake manifold from a brake booster; and performing an air-fuel ratio control based on the corrected intake air amount.

Abstract: A method for an alternate control of a continuously variable valve duration (CVVD) malfunction may include a CVVD failsafe control to resolve a calculation error of a cylinder charge amount due to a hardware failure of a CVVD system with the cylinder charge amount determined by any one of flow rate alternate, flow rate deviation correction, and valve duration update if the hardware failure is recognized by a CVVD controller, and to apply the cylinder charge amount to secure an air amount for a combustion chamber.

Abstract: A method and apparatus for calculating an internal exhaust gas recirculation (EGR) amount of an engine include a continuously variable valve duration (CVVD) apparatus. The internal EGR amount is calculated by correcting a backflow gas amount based on a valve duration changed by operation of the continuously variable valve duration apparatus during valve overlap of an intake valve or an exhaust valve.

Abstract: A method for correction of intake pulsation is provided. The method includes calculating a basic air charge amount of a cylinder or a charge amount conversion coefficient based on a measurement value of a sensor disposed in an intake system of an engine. A basic pulsation compensation coefficient for correcting an intake amount from a basic waveform of pulsation is calculated based on opening/closing of an intake valve and engine RPM. The basic pulsation compensation coefficient is then corrected when the basic waveform of the pulsation is changed.

Abstract: A method of removing impurities from EGR by air blowing may include performing an air-blowing mode in which, when a current intake system pressure detected by a controller exceeds a target intake system pressure in an intake system, in which a mixture is supplied to an engine, a portion of the mixture, serving as compressed air, flows into an EGR path, through which a portion of exhaust, serving as EGR gas and flowing in the intake system and an exhaust system connected to the intake system, is supplied to the engine.

Abstract: A method for avoiding a measurement error of an air flow sensor for a vehicle includes an engine control unit (ECU) which predicts, in advance, occurrence of the contamination by foreign materials included in the air or condensation of moisture on a sensor measurement plate of the air flow sensor, and performs an operation for preventing the contamination by foreign materials or the condensation of moisture when the occurrence is predicted, to avoid the measurement error of the air flow sensor due to the contamination by foreign materials or the condensation of moisture on the sensor measurement plate.

Abstract: The present invention relates to a method for diagnosing a failure of a power stage of an electronic waste gate actuator (EWGA). According to the present invention, whether the failure of the power stage of the EWGA occurs is determined by confirming, by an engine control unit (ECU), information on the failure of the power stage transferred from an EWGA driver IC at the time of EWGA position learning, after an engine is turned off. By doing so, even when a turbo-charger is not used for a long time, whether the failure of the power stage of the EWGA occurs may be diagnosed for every driving cycle, such that a failure of the ECU may be prevented in advance and unnecessary replacement of components may be prevented, thereby decreasing maintenance costs for a vehicle.

Abstract: A method for correction of intake pulsation is provided. The method includes calculating a basic air charge amount of a cylinder or a charge amount conversion coefficient based on a measurement value of a sensor disposed in an intake system of an engine. A basic pulsation compensation coefficient for correcting an intake amount from a basic waveform of pulsation is calculated based on opening/closing of an intake valve and engine RPM. The basic pulsation compensation coefficient is then corrected when the basic waveform of the pulsation is changed.

Abstract: A method and apparatus for calculating an internal exhaust gas recirculation (EGR) amount of an engine include a continuously variable valve duration (CVVD) apparatus. The internal EGR amount is calculated by correcting a backflow gas amount based on a valve duration changed by operation of the continuously variable valve duration apparatus during valve overlap of an intake valve or an exhaust valve.

Abstract: The present invention relates to a method for diagnosing a failure of a power stage of an electronic waste gate actuator (EWGA). According to the present invention, whether the failure of the power stage of the EWGA occurs is determined by confirming, by an engine control unit (ECU), information on the failure of the power stage transferred from an EWGA driver IC at the time of EWGA position learning, after an engine is turned off. By doing so, even when a turbo-charger is not used for a long time, whether the failure of the power stage of the EWGA occurs may be diagnosed for every driving cycle, such that a failure of the ECU may be prevented in advance and unnecessary replacement of components may be prevented, thereby decreasing maintenance costs for a vehicle.

Abstract: A method of removing impurities from EGR by air blowing may include performing an air-blowing mode in which, when a current intake system pressure detected by a controller exceeds a target intake system pressure in an intake system, in which a mixture is supplied to an engine, a portion of the mixture, serving as compressed air, flows into an EGR path, through which a portion of exhaust, serving as EGR gas and flowing in the intake system and an exhaust system connected to the intake system, is supplied to the engine.