Abstract: A waste heat recovery system may include a pump, first and second heat exchangers, an expander, and a valve. The first heat exchanger receives working fluid from the pump. The expander receives working fluid from the first heat exchanger and includes an output shaft that is powered by the flow of working fluid through the expander. The second heat exchanger may include a first fluid path and a second fluid path that is shorter than the first fluid path. The valve controls fluid flow through the first and second fluid paths. A sensor may measure a parameter of the working fluid that indicates whether the working fluid is in a gaseous state, a liquid state or a mixture of gas and liquid. A control module in communication with the sensor may control a position of the valve based on a value of the parameter measured by the sensor.

Abstract: Methods and systems for metering at least one EGR valve to a position determined to pass a desired EGR flow for a given set of engine characteristics. The methods include determining the EGR valve position based on pipe flow characteristics, or determining the EGR valve position based on pipe flow characteristics when differential pressure across the EGR valve is less than a pressure threshold.

Abstract: Methods and systems for metering at least one EGR valve to a position determined to pass a desired EGR flow for a given set of engine characteristics. The methods include determining the EGR valve position based on pipe flow characteristics, or determining the EGR valve position based on pipe flow characteristics when differential pressure across the EGR valve is less than a pressure threshold.

Abstract: An arrangement for determining purge valve flow tolerance for use with evaporative emissions control systems includes developing an equation based on data relating purge valve duty cycle to flow, wherein the equation describes a flow curve with reference to a first axis and a second axis. The arrangement further includes using the equation as a base equation for flow, and adapting the equation for part-to-part tolerance as a function of an intercept point of the equation with respect to the first axis, wherein the first axis relates to duty cycle.

Abstract: An arrangement for determining purge valve flow tolerance for use with evaporative emissions control systems includes developing an equation based on data relating purge valve duty cycle to flow, wherein the equation describes a flow curve with reference to a first axis and a second axis. The arrangement further includes using the equation as a base equation for flow, and adapting the equation for part-to-part tolerance as a function of an intercept point of the equation with respect to the first axis, wherein the first axis relates to duty cycle.

Abstract: A fuel control system is provided including a fuel tank and a purge vapor collection canister interconnected with an internal combustion engine. A purge vapor canister vent valve selectively seals the purge vapor canister from atmosphere such that the fuel tank, purge vapor canister, and engine intake manifold form a closed system. Upon a cold engine start, a purge valve disposed between the purge vapor canister and the engine intake manifold is opened such that the pressure differential between the engine intake manifold and the remainder of the system causes fuel vapor collected within the dome portion of the fuel tank to be drawn through the purge vapor canister and into the intake manifold. Simultaneously therewith, the amount of fuel injected by the fuel injectors to the engine is reduced such that a desired amount of total fuel delivery is established.

Abstract: A method is provided for controlling knock in an internal combustion engine. The method utilizes an adaptive control scheme to tailor knock thresholds to the current engine operating conditions, as well as to identify the cylinder in which the knocking condition occurred. The method utilizes a modified spark advance to alter the spark timing for the engine cylinders if a knocking condition is detected and a predetermined set of conditions has been met.

Abstract: A fuel control system is provided for enhancing the fueling strategy of a vehicle at start up when fueling is being supplemented with purge vapors from the fuel tank. The system includes monitoring the purge vapor flow rate from the purge vapor control system to the engine at start-up. A dynamic crankshaft fuel control fuel multiplier is then calculated based on engine roughness. If the engine is operating rough during purge vapor fueling, the amount of injected fuel is adjusted according to the fuel multiplier. Once oxygen sensor feedback is available, the dynamic crankshaft fuel control fuel multiplier is recalculated based on the oxygen sensor goal voltage. If necessary, the amount of injected fuel may be readjusted with the updated fuel multiplier. Once the engine is warm, the purge vapor fueling stops and the present methodology ends.

Abstract: A method is provided for controlling the delivery of fuel to an engine of an automotive vehicle equipped with a dynamic crankshaft fuel control system and an oxygen sensor feedback based fuel control system. The method includes determining an averaged combustion metric from the dynamic crankshaft fuel control system. The combustion metric is compared to an allowable engine roughness value and a dynamic crankshaft fuel control fuel multiplier is adjusted based on the comparison via a proportional-integral-derivative control calculation. Thereafter, the integral term of the dynamic crankshaft fuel control system's proportional-integral-derivative control calculation is stored.

Abstract: A method and corresponding system for optimizing performance of an internal combustion engine. The present invention senses gases emitted from engine combustion chambers via a first gas sensor and senses gases emitted from said engine combustion chambers subsequent to said gases passing through an engine catalytic converter via a second gas sensor. The temperatures of said first and second gas sensors are then sensed through data output from first and second gas sensors and temperature sensors. The first and second gas sensors are linearized in response to the sensed temperatures of the first and second gas sensors. The fuel level input into the engine combustion chambers is adjusted in response to linearizing of the first and second gas sensors.

Abstract: A methodology of computing a learned combustion stability value and applying the learned combustion stability value to control engine operation is provided. Engine speed is sensed for each expected firing of individual cylinders of the engine. The difference in engine speed for a selected cylinder firing and a cylinder firing occurring two cylinder firings earlier is determined to provide an expected acceleration value. The difference between successive expected acceleration values is computed. A learned combustion related value is determined as a function of the difference in the successive learned acceleration values and is an indication of engine roughness. The operation of the engine is controlled as a function of the learned combustion related value. The learned combustion stability value is advantageously employed so as to modify the fuel injection to an internal combustion engine, especially following a cold engine start so as to reduce hydrocarbon emissions.

Abstract: A method of adjusting idle spark for an individual cylinder of an internal combustion engine in an automotive vehicle including the steps of determining a crankshaft acceleration for an individual cylinder of the internal combustion engine and determining an average acceleration error for the individual cylinder based on the determined crankshaft acceleration. The method also includes the steps of determining an adaptive spark advance for the individual cylinder based on the determined average acceleration error and determining a new spark advance for the individual cylinder based on the determined adaptive spark advance and a nominal spark advance. The method further includes the steps of adjusting idle spark for the individual cylinder based on the new spark advance for the individual cylinder.

Abstract: A method for advanced crank spark with blend spark retard for an internal combustion engine includes the steps of selecting whether a spark in an engine cylinder will be fired on a predetermined first or second crank edge during an engine start mode, firing the spark on the second crank edge during the engine start mode if the second crank edge is selected, firing the spark on the first crank edge if the first crank edge is selected, determining whether the internal combustion engine is in the engine start mode based on engine speed, continuing to select whether to fire the spark on the predetermined first crank edge or the predetermined second crank edge if the internal combustion engine is in the engine start mode based on engine speed less than the predetermined speed, and retarding the spark from a first spark level to a hold start level at a predetermined rate, holding the spark at the hold spark level for a hold period, and advancing the spark to the first spark level at the predetermined rate, if the i

Abstract: A method of altitude compensation of exhaust gas recirculation in an intake manifold for an internal combustion engine includes the steps of calculating vacuum at sea level, calculating vacuum at present altitude of the engine, determining whether the calculated vacuum at sea level is equal to the calculated vacuum at present altitude, and correcting the exhaust gas recirculation in the intake manifold if the calculated vacuum at sea level does not equal the calculated vacuum at present altitude.

Abstract: A method of estimating exhaust gas recirculation in an intake manifold for an internal combustion engine includes the steps of determining a volumetric efficiency value of the intake manifold, determining whether a speed of the engine is accelerating, getting a manifold unfilling constant if the speed of the engine is not accelerating, getting a manifold filling constant if the speed of the engine is accelerating, calculating a K-factor based on the volumetric efficiency value and either the manifold filling constant or manifold unfilling constant, and using the K-factor to modify spark of the engine.

Abstract: A method of throttle fuel lean-out for an internal combustion engine including the steps of sensing a throttle position of a throttle for the engine with a throttle position sensor, calculating a delta throttle value based on the sensed throttle position, determining whether the engine is in a throttle deceleration condition based on the calculated delta throttle value, linearizing the change in throttle position with respect to absolute throttle position and engine speed if the engine is in a throttle deceleration condition, calculating a throttle deceleration fuel lean-out multiplier value based on the linearized change in throttle position, and applying the calculated throttle deceleration fuel lean-out multiplier value to a fuel pulsewidth value of fuel injectors for the engine and reducing the amount of fuel injected into the engine by the fuel injectors.

Abstract: A method of load and speed modifying on fuel lean-out for an internal combustion engine includes the steps of sensing a speed of the engine, determining an engine speed modifier as a function of current sensed engine speed, sensing a manifold absolute pressure (MAP) of an intake manifold of the engine, determining an engine load modifier as a function of current sensed MAP, adding the determined engine speed modifier and engine load modifier together to yield a speed/load modifier, and applying the speed/load modifier value to a fuel pulsewidth value of fuel injectors for the engine and reducing the amount of fuel injected into the engine by the fuel injectors.

Abstract: A method of averaging coolant temperature for an internal combustion engine in an automotive vehicle includes the steps of sensing coolant temperature of the engine based on an output signal of a coolant temperature sensor, determining an initial value of coolant temperature based on the output signal from the coolant temperature sensor, storing the determined initial value as an initial coolant temperature value (CLTMP1) and as an averaged coolant temperature value (AVCT), periodically updating the AVCT value, and using the AVCT value to control the output of fuel injectors of the engine.

Abstract: A method of catalyst purging (run-time) fuel lean-out for an internal combustion engine including the steps of determining whether the engine is in a throttle deceleration condition or a MAP deceleration condition, sensing a speed of the engine, determining whether the current sensed engine speed is above a predetermined speed if the engine is in a throttle or MAP deceleration condition, determining a magnitude of a run-time lean-out multiplier (RTLEAN) value if the current sensed engine speed is above the predetermined speed, and applying the determined RTLEAN value to a fuel pulsewidth value of fuel injectors for the engine and reducing the amount of fuel injected into the engine by the fuel injectors.

Abstract: A method of proportional deceleration fuel lean-out for an internal combustion engine includes the steps of sensing a throttle position of a throttle for the engine with a throttle position sensor, calculating a throttle proportional deceleration fuel lean-out multiplier (LOTHR) value based on the sensed throttle position, sensing a manifold absolute pressure (MAP) of an intake manifold for the engine with a MAP sensor, calculating a MAP proportional deceleration fuel learn-out multiplier (LOMAP) value based on the sensed MAP, combining the LOTHR and LOMAP values and calculating an overall proportional deceleration fuel lean-out multiplier (LOMULT) value, and applying the calculated LOMULT value to a fuel pulsewidth value of fuel injectors for the engine and reducing the amount of fuel injected into the engine by the fuel injectors.