Provided are a novel exhaust pipe temperature estimation device and a sensor heater control apparatus for an exhaust gas sensor using the same that accurately estimates an estimation exhaust pipe temperature when an internal combustion engine is stopped and restarted in response to a change of an environmental condition of the internal combustion engine and controls an operation of a sensor heater based on the estimated estimation exhaust pipe temperature. Thus, at least first correction information Tz based on a change of an exhaust pipe temperature and an elapsed time at stop, second correction information Ty based on a change of an internal combustion engine temperature at the stop of the internal combustion engine, and third correction information Tz based on a change of a cooling degree due to outdoor air during stop from the stop to restart are obtained, an estimation exhaust pipe temperature at the stop is corrected using at least one or more pieces of the correction information at restart of the internal combustion engine to estimate an estimation exhaust pipe temperature at the restart, and an estimation exhaust pipe temperature during an operation of the internal combustion engine thereafter is obtained using the estimation exhaust pipe temperature as an initial value, and further, a heating operation of a sensor heater is started when the estimation exhaust pipe temperature becomes equal to or higher than a predetermined value.

A method for controlling a vehicle includes: receiving a detection signal to perform an idle stop and go (ISG) function; and controlling the vehicle to enter into an ISG state where a fuel supply to an engine is cut off and the engine stops when the vehicle decelerates or stops in response to the detection signal. The detection signal includes a fuel cut off signal that is in on state when the vehicle decelerates and in off state at a reference revolution per minute (RPM) of the engine, a gear engagement signal, and a brake pedal signal indicating whether the brake pedal of the vehicle is operated. A controller of the vehicle generates an ISG entry signal based on the fuel cut off signal, the gear engagement signal, and the brake pedal signal to enter the vehicle into the ISG state.

A method for controlling a vehicle includes: receiving a detection signal required to perform an idle stop and go (ISG) function; and controlling the vehicle to enter into an ISG state where a fuel supply to an engine is cut off and the engine stops when the vehicle decelerates or stops in response to the detection signal. The detection signal includes a fuel cut off signal in on state when the vehicle decelerates and in off state at a reference revolution number of the engine, a gear engagement signal, a clutch pedal signal indicating whether a clutch pedal operating a clutch is operated, and a brake pedal signal indicating whether a brake pedal is operated. A controller generates an ISG entry signal based on the fuel cut off signal, the gear engagement signal, the clutch pedal signal, and the brake pedal signal to enter the vehicle into the ISG state.

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.

Methods and systems are provided for rationalizing an engine knock sensor. In one example, a method may include, responsive to an indication of an engine knock event, correlating an output of the engine knock sensor with an output of an on-board microphone to determine degradation of the engine knock sensor. By rationalizing the engine knock sensor against another on-board sensor (e.g., the on-board microphone), diagnostic fidelity may be increased.

An engine control apparatus determines that a piston is at a compression top dead center immediately before engine speed of an engine becomes zero if of the engine speed at the compression top dead center of the engine in a rotation drop period while the engine speed drops to zero after combustion of the engine is stopped. In the case where it is determined that the piston is at the compression top dead center immediately before the engine speed of the engine becomes zero, the engine control apparatus applies counter torque by the rotating electrical machine from the compression top dead center to stop the piston at a rotation angle position in a first half period of expansion process by application of the counter torque.

An engine control device includes an electronic control unit. The electronic control unit is configured to perform a spark discharge with an ignition plug for each cylinder by cutting off energization after elapse of a predetermined period from start of energization to an ignition coil for each cylinder of the engine, to stop the spark discharge caused by the ignition plug for each cylinder after supply of fuel to the engine is stopped when operation of the engine is stopped, and to control an ignition plug so as to stop the spark discharge caused by the ignition plug from a cylinder after a rotation speed of a crankshaft decreases gradually and the rotation speed of the crankshaft reaches a preset threshold value or less, after the stop of the supply of fuel to the engine.

An engine control device includes an electronic control unit. The electronic control unit is configured to perform a spark discharge with an ignition plug for each cylinder by cutting off energization after elapse of a predetermined period from start of energization to an ignition coil for each cylinder of the engine, to stop the spark discharge caused by the ignition plug for each cylinder after supply of fuel to the engine is stopped when operation of the engine is stopped, and to control an ignition plug so as to stop the spark discharge caused by the ignition plug from a cylinder after a rotation speed of a crankshaft decreases gradually and the rotation speed of the crankshaft reaches a preset threshold value or less, after the stop of the supply of fuel to the engine.

In a control system for an internal combustion engine which stops the rotation of an internal combustion engine by applying a counter torque thereto, the generation of noise or vibration accompanying the stop of rotation of the internal combustion engine is suppressed as much as possible. In the control system provided with a controller being adapted to stop the rotation of the internal combustion engine by carrying out forced stop processing in which the counter torque is inputted, in cases where the forced stop processing is carried out after the completion of the execution of specific motoring processing, the controller makes the counter torque at a certain timing before the counter torque becomes a predetermined torque after the start of the execution of the forced stop processing smaller than in the case where the forced stop processing is carried out without carrying out the specific motoring processing.

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.