Abstract: Fueling to one cylinder of an engine is selectively adjusted based on a correction associated with the cylinder. An instability module increments a counter value when the correction is equal to one of a first predetermined value and a second predetermined value and was previously equal to the other one of the first and second predetermined values. The instability module selectively generates a first indicator based on the counter value. A variance of imbalance values can be determined based on samples of an exhaust gas oxygen signal. Two variances are determined: one variance with adjustment based on the correction, one without adjustment based on the correction. A variance checking module selectively generates a second indicator based on the first and second variances. A re-synchronization module re-synchronizes the imbalance values with the cylinders, respectively, in response to generation of the first indicator and/or the second indicator.

Abstract: A system according to the principles of the present disclosure includes a timing control module and a diagnostic module. The timing control module controls engine valve timing by sending fluid to an advancing chamber of a cam phaser to adjust the cam phaser to an advanced position and by sending fluid to a retarding chamber of the cam phaser to adjust the cam phaser to a retarded position. The diagnostic module identifies a fault in a variable valve lift (VVL) mechanism based on a first difference between an advancing pressure of the advancing chamber and a retarding pressure of the retarding chamber.

Abstract: A technique can include receiving, at a controller for a vehicle, the controller including one or more processors, a signal indicative of a pressure in an intake manifold of an engine of the vehicle. The vehicle can include a supercharger configured to supply pressurized air to the intake manifold. The supercharger can be driven by a crankshaft of the engine via a belt. The technique can include estimating, at the controller, a frequency of the signal to obtain an estimated frequency. The technique can include determining, at the controller, whether the belt is slipping based on a comparison between the estimated frequency and a predetermined frequency. The technique can also include outputting, at the controller, a notification when the belt is determined to be slipping.

Abstract: A technique can include receiving, at a controller for a vehicle, the controller including one or more processors, a signal indicative of a pressure in an intake manifold of an engine of the vehicle. The vehicle can include a supercharger configured to supply pressurized air to the intake manifold. The supercharger can be driven by a crankshaft of the engine via a belt. The technique can include estimating, at the controller, a frequency of the signal to obtain an estimated frequency. The technique can include determining, at the controller, whether the belt is slipping based on a comparison between the estimated frequency and a predetermined frequency. The technique can also include outputting, at the controller, a notification when the belt is determined to be slipping.

Abstract: A control system for an engine is presented. The control system can include a transition period waveform monitor module, a stuck fuel injector detection module, and a fuel injection control module. The transition period waveform monitor module measures an electrical signal of a fuel injector upon deactivation of the fuel injector. The stuck fuel injector detection module detects a stuck fuel injector when an accumulated deviation of the electrical signal from a parameterized estimated reference waveform is outside of a predetermined range. The fuel injection control module controls fuel injection in the engine based on the detection of the stuck fuel injector.

Abstract: A system for diagnosing a switchable roller finger follower (SRFF) and an oil control valve (OCV) includes a signal monitoring module and a fault detection module. The signal monitoring module receives at least one of an individual cylinder fuel correction (ICFC) signal and an air/fuel ratio imbalance (AFIM) signal when: an engine speed signal is within a predetermined range of speed; an engine load signal is within a predetermined range of load; and a charcoal canister vapor signal is within a predetermined range of flow rate. The fault detection module detects a fault of at least one of a SRFF and an OCV based on an exhaust gas recirculation value and at least one of the ICFC and AFIM signals. The ICFC and AFIM signals are generated based on: an engine position signal; and at least one of an oxygen signal and a wide range air fuel signal.

Abstract: An air/fuel imbalance (AFIM) diagnostic system comprises a first module, an imbalance determination module, and an imbalance diagnostic module. The first module outputs imbalance data samples based on an oxygen signal provided by an oxygen sensor measuring oxygen in exhaust expelled from cylinders of a cylinder bank. The imbalance determination module determines an AFIM value based on the imbalance data samples. The imbalance diagnostic module selectively diagnoses an AFIM in the cylinder bank based on the AFIM value.

Abstract: A method and control module includes a manifold absolute pressure comparison module that determines a function of the manifold absolute pressure and an average manifold absolute pressure for a plurality of cylinders and that compares the manifold absolute pressure parameter to a manifold absolute pressure threshold. The control module includes a misfire event module that compares the misfire parameter to a misfire threshold. A hardware remedy module performs a valve actuation hardware remedy in response to comparing the manifold absolute pressure and comparing the misfire parameter.

Abstract: A system according to the principles of the present disclosure includes a timing control module and a diagnostic module. The timing control module controls engine valve timing by sending fluid to an advancing chamber of a cam phaser to adjust the cam phaser to an advanced position and by sending fluid to a retarding chamber of the cam phaser to adjust the cam phaser to a retarded position. The diagnostic module identifies a fault in a variable valve lift (VVL) mechanism based on a first difference between an advancing pressure of the advancing chamber and a retarding pressure of the retarding chamber.

Abstract: Fueling to one cylinder of an engine is selectively adjusted based on a correction associated with the cylinder. An instability module increments a counter value when the correction is equal to one of a first predetermined value and a second predetermined value and was previously equal to the other one of the first and second predetermined values. The instability module selectively generates a first indicator based on the counter value. A variance of imbalance values can be determined based on samples of an exhaust gas oxygen signal. Two variances are determined: one variance with adjustment based on the correction, one without adjustment based on the correction. A variance checking module selectively generates a second indicator based on the first and second variances. A re-synchronization module re-synchronizes the imbalance values with the cylinders, respectively, in response to generation of the first indicator and/or the second indicator.

Abstract: A method and system for controlling an engine includes a desired fuel mass determination module that determines fuel mass for injection into a cylinder. The system also includes a split determination module that splits the fuel mass into split fuel masses and a pulsewidth determination module that converts the split fuel masses into injection pulsewidths outside of an injector operation exclusion zone.

Abstract: A control system for a homogeneous charge compression ignition (HCCI) engine includes a fuel requirement estimation module, a torque estimation module, and a torque control module. The fuel requirement estimation module estimates a fuel requirement of the HCCI engine based on a desired indicated mean effective pressure (IMEP) of cylinders in the HCCI engine. The torque estimation module estimates a torque output of the HCCI engine based on the estimated fuel requirement. The torque control module adjusts the torque output of the HCCI engine based on the estimated torque output and a desired torque output.

Abstract: A control system for an engine is presented. The control system can include a transition period waveform monitor module, a stuck fuel injector detection module, and a fuel injection control module. The transition period waveform monitor module measures an electrical signal of a fuel injector upon deactivation of the fuel injector. The stuck fuel injector detection module detects a stuck fuel injector when an accumulated deviation of the electrical signal from a parameterized estimated reference waveform is outside of a predetermined range. The fuel injection control module controls fuel injection in the engine based on the detection of the stuck fuel injector.

Abstract: A system includes an offset determination module and a correction determination module. The offset determination module determines an offset value based on an average response time of an exhaust gas oxygen (EGO) sensor located upstream of a catalyst in an exhaust system. The offset value relates one of a predetermined number of cylinder imbalance values to a cylinder of an engine. The correction determination module determines a fueling correction for the cylinder based on the offset value and one of the predetermined number of cylinder imbalance values.

Abstract: An engine control system for a homogenous charge compression ignition (HCCI) engine includes an airflow determination module and a sensor diagnostic module. The airflow determination module generates a first plurality of estimates of airflow into the HCCI engine when the HCCI engine is operating in a first combustion mode, wherein the first plurality of estimates are based on an intake manifold absolute pressure (MAP), a mass air flow (MAF) rate, and a camshaft position. The sensor diagnostic module determines a state of at least one of a first plurality of sensors based on a predetermined threshold and differences between one of the first plurality of estimates and others of the first plurality of estimates, wherein the first plurality of sensors includes a MAP sensor, a MAF sensor, and a camshaft sensor.

Abstract: A method and system for controlling an engine includes a normal individual cylinder fuel correction determination module determining normal pulse mode individual cylinder fuel corrections in a normal pulse mode. The system also includes a split pulse enable module operating the fuel injectors in split pulse mode having a linear pulse and a ballistic pulse smaller than the linear pulse. The system also includes a split pulse individual cylinder fuel correction determination module determining split pulse mode individual cylinder fuel corrections in the split pulse mode. The system also includes a ballistic pulse adaptation module adjusting ballistic pulse calibration values in response to the normal pulse mode individual cylinder fuel corrections and the split pulse mode individual cylinder fuel corrections to form adjusted ballistic pulse calibration values.

Abstract: A system includes an offset determination module and a correction determination module. The offset determination module determines an offset value based on an average response time of an exhaust gas oxygen (EGO) sensor located upstream of a catalyst in an exhaust system. The offset value relates one of a predetermined number of cylinder imbalance values to a cylinder of an engine. The correction determination module determines a fueling correction for the cylinder based on the offset value and one of the predetermined number of cylinder imbalance values.

Abstract: An engine control system for a homogenous charge compression ignition (HCCI) engine includes a fuel injector temperature determination module and a fuel injector control module. The fuel injector temperature determination module determines a temperature of a tip of a fuel injector based on a first temperature model when the HCCI engine is operating in an HCCI combustion mode, and determines the temperature of the tip of the fuel injector based on a second temperature model when the HCCI engine is operating in a spark ignition (SI) combustion mode. The fuel injector control module controls a fuel injector pulse width based on the determined temperature and a predetermined temperature threshold, wherein the fuel injector pulse width increases when the determined temperature is greater than the predetermined temperature threshold.

Abstract: A diagnostic system and method for operating the same includes a pressure monitoring module generating a diagnostic pressure signal and a camshaft driven engine component correction module generating an engine component oil pressure correction signal and generating a corrected diagnostic pressure signal based on the diagnostic pressure signal and the engine component oil pressure signal. The system further includes a diagnostic module generating a failed variable valve lift mechanism signal based on the corrected diagnostic pressure signal.

Abstract: A control system for a homogeneous charge compression ignition (HCCI) engine includes a fuel requirement estimation module, a torque estimation module, and a torque control module. The fuel requirement estimation module estimates a fuel requirement of the HCCI engine based on a desired indicated mean effective pressure (IMEP) of cylinders in the HCCI engine. The torque estimation module estimates a torque output of the HCCI engine based on the estimated fuel requirement. The torque control module adjusts the torque output of the HCCI engine based on the estimated torque output and a desired torque output.