Abstract: A method and system for estimating air mass per cylinder of an internal combustion engine is provided. An output signal from a MAF sensor is digitally processed to provide an estimate air mass per cylinder (APC). The system includes the MAF sensor; a data acquisition unit configured to receive an output signal from the MAF sensor and produce a sampled signal having a sampling rate greater than one sample per firing event; a multiple band pass (MBP) filter configured to remove signal components caused by airflow pulsations and oscillations through the MAF sensor; an envelope detector configured to detect the lower and upper envelopes of the MBP filtered signal; a MAF estimator configured to estimate a mass airflow based on the detected lower and upper envelopes; a signal decimator; a low pass filter; and a APC converter to converted the low pass filtered signal into an estimated APC.

Abstract: A method and system for estimating air mass per cylinder of an internal combustion engine is provided. An output signal from a MAF sensor is digitally processed to provide an estimate air mass per cylinder (APC). The system includes the MAF sensor; a data acquisition unit configured to receive an output signal from the MAF sensor and produce a sampled signal having a sampling rate greater than one sample per firing event; a multiple band pass (MBP) filter configured to remove signal components caused by airflow pulsations and oscillations through the MAF sensor; an envelope detector configured to detect the lower and upper envelopes of the MBP filtered signal; a MAF estimator configured to estimate a mass airflow based on the detected lower and upper envelopes; a signal decimator; a low pass filter; and a APC converter to converted the low pass filtered signal into an estimated APC.

Abstract: A method for cold start emissions diagnostic of a catalytic treatment device of an internal combustion engine includes determining a torque reserve; determining a catalyst light off (CLO) state; integrating the total torque reserve over a time period established by the CLO state; determining if a value from the integration exceeds an integration threshold; and if the value from the integration exceeds the integration threshold, indicating that the cold start emissions diagnostic is positive.

Abstract: A method for cold start emissions diagnostic of a catalytic treatment device of an internal combustion engine includes determining a torque reserve; determining a catalyst light off (CLO) state; integrating the total torque reserve over a time period established by the CLO state; determining if a value from the integration exceeds an integration threshold; and if the value from the integration exceeds the integration threshold, indicating that the cold start emissions diagnostic is positive.

Abstract: Rationality diagnostic techniques for an intake oxygen sensor are utilized to detect sensor malfunction. A non-intrusive diagnostic technique includes passively detecting when an exhaust gas recirculation (EGR) valve position crosses low/high position thresholds, whereas an intrusive diagnostic technique includes actively commanding the EGR valve to predetermined low/high positions. During a period after the EGR valve position reaches/crosses at least one of the low/high positions/position thresholds, respectively, maximum and minimum intake oxygen concentration is monitored. When the EGR valve position has crossed both the low/high positions/position thresholds and a difference between the maximum and minimum oxygen concentrations is less than a respective difference threshold, a malfunction of the intake oxygen sensor is detected. A malfunction indicator lamp (MIL) could be set to indicate the malfunction.

Abstract: Rationality diagnostic techniques for an intake oxygen sensor are utilized to detect sensor malfunction. A non-intrusive diagnostic technique includes passively detecting when an exhaust gas recirculation (EGR) valve position crosses low/high position thresholds, whereas an intrusive diagnostic technique includes actively commanding the EGR valve to predetermined low/high positions. During a period after the EGR valve position reaches/crosses at least one of the low/high positions/position thresholds, respectively, maximum and minimum intake oxygen concentration is monitored. When the EGR valve position has crossed both the low/high positions/position thresholds and a difference between the maximum and minimum oxygen concentrations is less than a respective difference threshold, a malfunction of the intake oxygen sensor is detected. A malfunction indicator lamp (MIL) could be set to indicate the malfunction.

Abstract: A method and arrangement is provided for estimating an initial value for an internal battery temperature of a vehicle using a four zone process that determines which of a predetermined set of time zones correlates with a measured period of time for an engine of the vehicle being in an engine-off condition. Once the time zone is determined, an initial estimated value of the internal temperature of the battery is determined as a function of a set of parameters correlated with the determined time zone. The set of time zones include a holding time zone, a model based estimation time zone which is greater in time than the holding time zone, a first self-adjustment zone which is greater in time than the model based estimation time zone, and a second self-adjustment time zone which is greater in time than the first self-adjustment time zone.