Abstract: Techniques for real-time virtual sensing of an axle assembly temperature include determining, at a controller of a vehicle, an initial temperature of an axle assembly of the vehicle based on an ambient temperature and a fluid temperature of a transmission. The techniques include determining, at the controller, an operating mode of the vehicle, the operating mode of the vehicle being one of moving and non-moving. The techniques also include estimating, at the controller, a temperature of the axle assembly based on the initial axle assembly temperature and the vehicle operating mode using an axle temperature model.

Abstract: Techniques for real-time virtual sensing of an axle assembly temperature include determining, at a controller of a vehicle, an initial temperature of an axle assembly of the vehicle based on an ambient temperature and a fluid temperature of a transmission. The techniques include determining, at the controller, an operating mode of the vehicle, the operating mode of the vehicle being one of moving and non-moving. The techniques also include estimating, at the controller, a temperature of the axle assembly based on the initial axle assembly temperature and the vehicle operating mode using an axle temperature model.

Abstract: A method for controlling slip in an EMCC equipped torque converter is provided. The method determines whether an EMCC slip rate exceeds a predetermined RPM, determines whether a crankshaft RPM acceleration exceeds a predetermined rate, reduces an output torque of an engine in response to one of said EMCC slip rate exceeding said predetermined RPM and said crankshaft RPM acceleration exceeding said predetermined rate; and disables said output torque of an engine in response to said EMCC slip rate being less than said predetermined RPM and said crankshaft RPM acceleration being less than said predetermined rate.

Abstract: The present invention provides a flexible fuel compensation system for determining the percent alcohol content of fuel in a flexible fueled vehicle at the instance of fueling and in an open loop operating mode. According to the invention, two estimated percent alcohol content values are calculated based on the old fuel mixture's alcohol content and two fueling possibilities. A first value is calculated for the possibility that E85 fuel was added to the tank and a second value is calculated for the possibility that E0 fuel was added to the tank. If the inferred ethanol content increases above a positive threshold during closed loop operation, the system assumes that E85 fuel has been added to the tank. Conversely, if the inferred ethanol content decreases below a negative threshold, the system assumes that E0 fuel was added to the tank.

Abstract: A method is provided for testing an evaporative emission control system for a missing or loose fuel cap comprising detecting a refueling event and running a leak detection test of the evaporative emission control system to determine if a large leak is present. If a large leak is detected, the methodology sets a fault code and activates a driver warning lamp indicating a potential cap sealing problem. The leak detection test is repeatedly re-executed after the large leak is detected to determine when the large leak condition ceases. When the large leak condition ceases, the previously set fault code is removed and the driver warning lamp is deactivated. If the large leak does not cease and is detected again after the next refueling event when an opportunity for resealing the cap existed, a new fault code is set indicating that the potential cap sealing problem is a persistent problem so that the integrity of the evaporative system may need to be tested.

Abstract: A method is provided for triggering a system for learning the percent alcohol content of a fuel used in a motor vehicle capable of operating on more than one type of fuel. The fuel composition learning system is triggered each time fuel is added to the vehicle's fuel tank, each time the engine is started when the fuel volume in the fuel tank falls below a given value or if a fuel level sending unit malfunction has been detected. The fuel composition learning system is also triggered if an error is detected in the value of the learned percent alcohol content of the fuel.

Abstract: The present invention provides a flexible fuel compensation system for determining the percent alcohol content of fuel in a flexible fueled vehicle at the instance of fueling and in an open loop operating mode. According to the invention, two estimated percent alcohol content values are calculated based on the old fuel mixture's alcohol content and two fueling possibilities. A first value is calculated for the possibility that E85 fuel was added to the tank and a second value is calculated for the possibility that E0 fuel was added to the tank. If the inferred ethanol content increases above a positive threshold during closed loop operation, the system assumes that E85 fuel has been added to the tank. Conversely, if the inferred ethanol content decreases below a negative threshold, the system assumes that E0 fuel was added to the tank.

Abstract: The present invention provides a flexible fuel compensation system for controlling operating parameters of an internal combustion engine based on a learned value of the percent alcohol content of the fuel using an oxygen feedback system. The methodology determines a fuel composition multiplier based on the percent alcohol content and implements gasoline operating parameters for the internal combustion engine if the fuel composition multiplier is less than a first threshold value, mixed gasoline/alcohol operating parameters if the fuel composition multiplier is greater than the first threshold value, and high concentration alcohol operating parameters if the fuel composition multiplier is greater than a second threshold value for a number of comparison checks. After a predetermined period, the fuel composition multiplier is updated and re-compared to the first and second thresholds and the appropriate one of the aforementioned operating parameters is implemented.

Abstract: A method of leak detection for an evaporative emission control system during periods of low engine vacuum includes the steps of pulsing a leak detection pump at a predetermined rate and determining whether engine vacuum level is low. The method also includes the steps of maintaining pressurization of the evaporative emission control system if the engine vacuum level is low, maintaining pressurization behind a vapor canister vent valve if the engine vacuum level is low, and detecting for leaks in the evaporative emission control system after a normal engine vacuum level is attained.

Abstract: A method of de-pressurizing an evaporative emission control system includes the steps of pulsing a leak detection pump at a predetermined rate and purging accumulated vapors from a vapor canister. The method also includes the steps of determining whether a last pump period is greater than or equal to a predetermined system de-pressurization mode pump period and continuing the method if the last pump period is less than the system de-pressurization mode pump period.

Abstract: A method of leak detection for an evaporative emission control system to determine if a leak is present in a portion of the system includes the steps of energizing a leak detection pump to close a canister vent control valve of the system and pressurize the system, and determining whether a possible pinched line of the system has occurred.

Abstract: A method of checking for purge flow in an evaporative emission control system includes the steps of determining if there is a fault in a leak detection pump, de-energizing the leak detection pump if there is a fault, and determining the state of a leak detection pump switch. The method also includes the steps of concluding a pump switch closed state if the pump switch is not opened, concluding a pump switch opened state if the pump switch is not closed, and monitoring a purge duty cycle until the evaporative emission control system is depressurized.

Abstract: A method of pinched line detection for an evaporative emission control system to determine if a pinched line is present within the system includes the steps of pulsing a leak detection pump at a predetermined rate and determining if a last pump period is less than a predetermined possible pinched line period limit. The method also includes the steps of concluding a possible pinched line if the last pump period is not less than the possible pinched line period limit and concluding that there is not a possible pinched line if the last pump period is greater than or equal to the possible pinched line period limit.

Abstract: A method of testing an evaporative emission control system to determine if the evaporative emission control system has reached a predetermined pressure includes the steps of pulsing a leak detection pump at a predetermined rate and determining if a last pump period is greater than or equal to a predetermined test mode period threshold. The method also includes the steps of pressurizing the evaporative emission control system if the last pump period is less than a test mode period threshold and continuing the method if the last pump period is equal to or greater than the test mode period threshold.

Abstract: A method of controlling a purge solenoid for a purge control system of an internal combustion engine is provided. The method includes the steps of determining whether predetermined conditions are right for duty cycling the purge solenoid and turning the purge solenoid OFF if predetermined conditions are not right and obtaining a duty cycle for the purge solenoid based on a duty cycle flow (DCFLOW) if predetermined conditions are right. The method also includes the steps of determining an output level of the purge solenoid based on the obtained duty cycle and controlling the purge solenoid to the obtained duty cycle.