A method for detecting valve leakage of a least one valve at a cylinder intake manifold or exhaust manifold of a vehicle engine, the method comprising: acquiring a set of pressure data points indicative of the pressure in the cylinder intake manifold or exhaust manifold for crankshaft angular positions covering crankshaft angular rotation degrees such that each of the at least one valve has opened at least one time; and determining at least one test value based on the set of pressure data points, wherein a valve leakage is detected based on a comparison of the at least one test value to a threshold value.

An injection control device of capable of correcting an energization time even in an S/N non-guaranteeable situation includes: an energization controller calculating an energization time correction amount based on an area correction performed by an energization time correction amount calculator regarding electric current flowing in a fuel injection valve when the fuel injection valve is electrically driven for injecting fuel; and an energization instruction time calculator correcting an energization instruction time for fuel injection in a next cycle and thereafter by using the energization instruction time correction amounts in or before a current cycle.

Methods and systems for calculating a plurality of aging factors in a system operating an engine. The calculated aging factors may include one or more of fuel injector drift, exhaust gas recirculation valve obstruction, and mass air flow sensor bias. Mass flow throughout the system, and pressures and temperatures within the system, are observed in an approach that relies on mass preservation concepts to estimate drift, obstruction and bias estimates.

Methods and systems that monitor an actuator state of wear. One or more observations are made as to one or more extremum positions of the actuator to determine a reference extremum position when the actuator is not worn. As the actuator becomes worn, the difference between a present extremum position and the reference is used to monitor actuator wear. Actuator wear may be observed to identify or predict a need for maintenance or replacement, and/or may be used in determining health impacts of control system solutions.

The disclosure relates to a method for operating an internal combustion engine which has at least one injector and in which a correction of fuel injection quantity is implemented. For the correction of the fuel injection quantity, different properties of the injector in the ballistic working range thereof and in the linear working range thereof are evaluated. A total injection quantity of the injector demanded in an operating cycle is divided into a number of smaller, equal partial injection quantities implemented as partial pulses, and an evaluation of the pressure drops triggered by the partial pulses is performed in the correction of the fuel injection quantity. The disclosure furthermore relates to a device for operating an internal combustion engine which has at least one injector and in which a correction of the fuel injection quantity is implemented.

Methods and systems are provided for diagnostics of an exhaust tuning valve during vehicle-off conditions. In one example, the engine may be reverse rotated, unfueled while the position of the exhaust is varied and an intake air flow is estimated at each position of the exhaust tuning valve. The exhaust tuning valve may be diagnosed based on a change in air flow with the variation in the position of the exhaust tuning valve.

The invention relates to a method for operating an internal combustion engine with fuel which is combusted using a spark plug. According to the invention, the aging of the spark plug, in particular the aging of an electric resistor of the spark plug, is monitored during the operation of the internal combustion engine, wherein electromagnetic radiation of the spark plug is detected for monitoring purposes. The invention additionally relates to a controller for carrying out the method.

A method for verifying a CVVD location learning result may include performing a learning value verification control by confirming a position of a control shaft connected to a motor with a signal value of an auxiliary cam sensor for a rotation of a camshaft if a controller determines that a learning value acquired in a short duration and a long duration of a CVVD system is desired to be verified.

Methods and systems are provided for monitoring a status of a heater core isolation valve (HCIV) housing in an engine coolant circuit including a first coolant loop and a second coolant loop. In one example, a method may include indicating degradation of the HCIV based on a difference between a first coolant loop temperature and a second coolant loop temperature upon activation of coolant system pumps and deactivation of a positive temperature coefficient (PTC) heater housed in the cabin heating loop.

In a method of removing particles in an injector of a diesel engine, a stop of the diesel engine may be recognized. An injection signal may be inputted into the injector of the stopped diesel engine. A control valve of the injector may be moved in a low-pressure passage by the injection signal to remove the particles accumulated on an inner wall of the low-pressure passage. Thus, a malfunction of the control valve caused by the particles may be previously prevented.