A method and system for operating a vehicle that includes an integrated starter/generator and a driveline disconnect clutch is described. In one example, the method estimates engine torque as a function of engine temperature during cold engine starts so that if an estimate of engine torque is in error, the integrated starter/generator may still successfully start the engine.

A method and system for operating a vehicle that includes an integrated starter/generator and a driveline disconnect clutch is described. In one example, the method estimates engine torque as a function of engine temperature during cold engine starts so that if an estimate of engine torque is in error, the integrated starter/generator may still successfully start the engine.

Disclosed is a method for determining the engine torque delivered by a multi-cylinder engine, including the following steps: determining the angular velocity of the crankshaft and measuring the cylinder pressure over an angular window of combustion in a first cylinder fitted with a cylinder pressure sensor; calculating the value of the engine torque (TQI.sub.ref) in this window; determining a current transfer function for the learning of the torque, so as to estimate the torque TQI.sub.mdl(cyl)) in a second cylinder not fitted with a cylinder pressure sensor, from the product of: the engine torque calculated over the angular window of the first cylinder, a ratio between: the angular velocity of the crankshaft over an angular window of combustion of the second cylinder, and the angular velocity of the crankshaft over the window of combustion of the first cylinder.

Disclosed is a method for determining the engine torque delivered by a multi-cylinder engine, including the following steps: determining the angular velocity of the crankshaft and measuring the cylinder pressure over an angular window of combustion in a first cylinder fitted with a cylinder pressure sensor; calculating the value of the engine torque (TQI.sub.ref) in this window; determining a current transfer function for the learning of the torque, so as to estimate the torque TQI.sub.mdl(cyl)) in a second cylinder not fitted with a cylinder pressure sensor, from the product of: the engine torque calculated over the angular window of the first cylinder, a ratio between: the angular velocity of the crankshaft over an angular window of combustion of the second cylinder, and the angular velocity of the crankshaft over the window of combustion of the first cylinder.

In one embodiment, a method of determining correct engine phase in an internal combustion engine without a cam sensor, the engine having a plurality of piston-cylinders that cause rotation of a crankshaft and a fuel delivery assembly associated with each of the plurality of piston-cylinders, the method comprising monitoring an engine parameter, modifying an amount of fuel delivered to a known piston-cylinder, advancing a spark time one of the plurality of piston-cylinders, and determining an actual engine phase based on a change in the engine parameter.

In one embodiment, a method of determining correct engine phase in an internal combustion engine without a cam sensor, the engine having a plurality of piston-cylinders that cause rotation of a crankshaft and a fuel delivery assembly associated with each of the plurality of piston-cylinders, the method comprising monitoring an engine parameter, modifying an amount of fuel delivered to a known piston-cylinder, advancing a spark time one of the plurality of piston-cylinders, and determining an actual engine phase based on a change in the engine parameter.

Methods, apparatus, systems, and articles of manufacture are disclosed to monitor engine starting systems. An example apparatus includes processor circuitry to execute instructions to measure engine starting system data from a machine; determine a total starting crank time and an ambient air temperature for the machine from the engine starting system data; compare the engine starting system data using a machine learning model; model a relationship between the ambient air temperature and the total starting crank time; generate a score of an engine starting system from the machine learning model; determine comparison result from the relationship between the ambient air temperature and the total starting crank time; and display an alert to a user based on at least one of the score of the engine starting system or the comparison result from the relationship between the ambient air temperature and the total starting crank time.

Methods, apparatus, systems, and articles of manufacture are disclosed to monitor engine starting systems. An example apparatus includes processor circuitry to execute instructions to measure engine starting system data from a machine; determine a total starting crank time and an ambient air temperature for the machine from the engine starting system data; compare the engine starting system data using a machine learning model; model a relationship between the ambient air temperature and the total starting crank time; generate a score of an engine starting system from the machine learning model; determine comparison result from the relationship between the ambient air temperature and the total starting crank time; and display an alert to a user based on at least one of the score of the engine starting system or the comparison result from the relationship between the ambient air temperature and the total starting crank time.

A method is for route identification that is conducive for successful diagnosis of an exhaust gas treatment system of a vehicle. In the method, an ECU in the vehicle receives a value of GPS coordinates from a GPS module, and the ECU retrieves a value of day, date, and time from an ECU clock. The ECU monitors a value of engine operating conditions with reference to the received value of GPS coordinates and the retrieved value of day, date, and time. The ECU identifies a segment of GPS coordinates for successful diagnosis of an exhaust gas treatment system based on the monitored value. Upon the identification, the segment of GPS coordinates is stored in ECU memory.

The present disclosure describes methods and systems for determining a flow of a combustible portion of vent gas delivered to an engine. The flow rate measurement may be performed by using the engine response to a relatively short (e.g. 1 to 5 s) reduction of the vent gas flow. A cross-correlation between RPM data of the engine and a reference signal corresponding to a state of a valve configured to reduce the vent gas flow is determined, and a flow rate of the combustible portion of the vent gas delivered to the engine is determined from the maximum value of the cross-correlation.