A system for starting an engine of a vehicle has a fuel injector injecting fuel into a closed intake port to form an air fuel mixture. The system also includes an actuator rotating a crankshaft in a first direction to open the intake port by moving a piston within a cylinder coupled to the crankshaft. A combustion chamber defines between the cylinder and the port receiving the air fuel mixture through the intake port. The actuator rotates the crankshaft in a second direction to close the intake port. A spark plug ignites the air fuel mixture to start the engine. The engine also includes many other disclosed features.

A method for diagnosing an engine system including a continuous variable valve duration (CVVD) apparatus, a driving unit of the CVVD apparatus including a first driving unit and a second driving unit, a CVVD position detector configured to detect a position of the CVVD apparatus, a camshaft position detector configured to detect a position of a camshaft, a front lambda detector configured to detect a lambda value at front of intake valve, and a controller may include the steps of starting the engine, detecting measured values of the front lambda detector during combustion of first to fourth cylinders (first to fourth lambda values), determining whether CVVD driving unit is misaligned according to the detected first to fourth lambda values, and generating a warning notification when the CVVD driving unit is determined to be misaligned.

Disclosed is a method for detecting the direction of rotation of a crankshaft of an engine of a motor vehicle. The detection method includes in particular, when the crankshaft is in a second predetermined angular position between a low angular position and a high angular position of the crankshaft, a step of commanding the closure of a control valve for the intake of fuel into the high-pressure pump, a step of measuring a second pressure value in the high-pressure rail, and a step of detecting a nominal direction of rotation of the crankshaft if the second pressure value measured is greater than or equal to an expected pressure value or of detecting a reverse direction of rotation of the crankshaft if the second pressure value measured is less than the expected pressure value.

An ignition performance increasing method of an automobile may include inputting a crank position sensor signal to detect a rotational position of a crankshaft of an engine, generating an engine angle tick, acquiring an engine synchronization by determining a position of the crankshaft and a position of a cam, setting a sync task at a specified position, and performing fuel injection and ignition.

A method for engine control under an entire driving range of a vehicle based on control timing prediction implemented in the vehicle is provided, which may reduce a start angle error calculated at a calculation time prior to an operation time when actual injection and ignition is performed by grasping a tooth period change tendency for a tooth period of a current time that injector/igniter drivers of an engine control unit read from an engine position management driver and calculating a start angle of fuel injection and ignition through prediction of the tooth period to match an actual operation time. In particular, since the prediction of the tooth period to match the actual operation time is based on a change tendency of the tooth period stored up to the current time, the injection and ignition time effectively reflects an engine operation situation in which an engine RPM is changed.

Methods and systems are provided for diagnosing a cylinder valve deactivation mechanism in an engine system having cam-actuated valves. Movement of a latch pin of the deactivation mechanism is inferred from an induction current generated by a solenoid coupled to the latch pin, and the inferred movement is used to diagnose operation of cylinder valve deactivation mechanism. The inferred movement and a profile of the induction current is also used to estimate camshaft and crankshaft timing for improved cylinder fuel delivery in the absence of a camshaft sensor.

A control system includes a controller. The controller estimates the swing-back amount indicating the turning amount of the crankshaft in the reverse rotation direction until the crankshaft stops. The controller calculates a stop-time counter value which is a value of a crank counter at the time when the engine is stopped based on a final counter value which is the value of the crank counter calculated last before the crankshaft stops and the estimated swing-back amount. The controller corrects the swing-back amount used for calculating the stop-time counter value based on a difference between the number of driving times calculated with reference to the map based on the calculated stop-time counter value and the value of the crank counter and the number of driving times calculated by increasing the number of driving times by one each time the high pressure system fuel pressure increases by the threshold or more.

A control system includes a controller. The controller counts the number of driving times of the high pressure fuel pump, which is the number of the reciprocating motions of the plunger based on a crank counter that is counted up at every predetermined crank angle. The controller stores a map in which a top dead center of the plunger is associated with a crank counter value, and store a crank counter value while an engine is stopped as a stop-time counter value. The controller calculates, referring to the map, the number of the crank counter values corresponding to the top dead center of the plunger between a crank counter value and the stop-time counter value, and set a calculated number as the number of driving times.

A control system includes a controller. The controller counts the number of driving times of a high pressure fuel pump, which is the number of reciprocating motions of a plunger based on a crank counter. The controller estimates a high pressure system fuel pressure based on the calculated number of driving times, a fuel temperature detected by a fuel temperature sensor, and a low pressure system fuel pressure detected by a low pressure system fuel pressure sensor when the high pressure system fuel pressure is not able to be acquired from a high pressure system fuel pressure sensor. The controller sets an opening period of an in-cylinder fuel injection valve based on the estimated high pressure system fuel pressure and to perform an engine start by an in-cylinder fuel injection when the high pressure system fuel pressure is not able to be acquired from the high pressure system fuel pressure sensor.

An engine synchronization method may include: detecting teeth numbers of crank teeth installed on a crankshaft based on a pulse signal generated from a crankshaft position sensor; calculating a tooth period between a falling edge and a next falling edge of the pulse signal generated from the crankshaft position sensor and detecting a missing tooth based on the calculated tooth period; determining whether the detected missing tooth is an actual missing tooth based on a tooth number detected at the time of detecting the missing tooth; and performing synchronization control of an engine when it is determined that the detected missing tooth is the actual missing tooth.