Abstract: A method and apparatus for executing a strategy of electronic throttle monitoring of a powertrain system including an electronic powertrain control module, and an electronic throttle control, includes an independent processor receiving signals shared with the powertrain control module from sensors and actuators on the vehicle. The monitor operates in a monitoring mode to detect faults occurring in the powertrain or the powertrain control module, and determines whether mitigating conditions occur in conjunction with detected power output greater than power demand. In the event that these mitigating conditions are not detected, the monitor operates in a limiting mode to actuate decreases in power output below the level of power demand.

Abstract: Systems which progress through a series of states or program steps, such as software controlled computers, are monitored by means of a watchdog timer which samples at least two check bits generated by a system being monitored with the check bits being generated such that only one can change its logic state between valid samples of the check bits. The monitored system is reset if a fault within the system results in an error in the normal sequence through the series of states or program steps such that more than one of the check bits changes from sample to sample. In addition, if the sequence becomes static such that no bits change within the check bits from sample to sample, a time-out will occur which also resets the monitored system. Preferably, the check bits are generated in accordance with Gray code.

Abstract: A fuel injection system used in the intake air passageway of an internal combustion engine has a strategy for reducing cold start hydrocarbon emissions. The fuel injector has an actuator which allows the fuel spray pattern to be varied from one which is widely dispersed and atomized to one which is only weakly dispersed. A strategy for varying the spray pattern during the engine warm-up period after cold start is disclosed. The strategy increases evaporation within the passageway so that cold start overfuelling and attendant hydrocarbon emissions are reduced.

Abstract: A method and system for determining a level of vapor generated by an evaporative system. The evaporative system is closed to atmosphere. An initial pressure in a fluid-filled tank is sensed and, after a predetermined amount of time, a second pressure in the tank is sensed. A pressure difference is determined based on the sensed initial pressure and the sensed second pressure. The level of vapor generated by the evaporative system is determined based on the pressure difference.

Abstract: A computer program architecture for a motor vehicle on-board diagnostic system includes a plurality of monitor modules for monitoring vehicle systems or components and issuing a malfunction subroutine call to a diagnostic executive upon detecting a system or component malfunction. The executive includes a plurality of software objects or modules for carrying out malfunction indicator light control and fault code storage strategies. A diagnostic scheduler module implemented as a finite state machine, controls and coordinates the sequence of the test to be run by the monitor modules as well as on-demand self tests. A malfunction indicator light (MIL) control module implements four distinct light control strategies through finite machines for illuminating and extinguishing the light and for storing and erasing fault codes under predetermined conditions.

Abstract: A system and method for engine idle speed control delay operation of a vehicle accessory (26) while introducing a stored torque disturbance profile corresponding to that vehicle accessory into a feedforward engine control system so as to minimize variation of engine idle speed. Torque disturbances resulting from operation of an alternator (32), power steering pump (28), or air conditioning compressor and blower (30) are characterized and stored in the memory of an electronic control module (22). When a request for operation of an accessory is detected, the stored profile is fed into the control system prior to actual operation of the accessory so as to reduce or eliminate control system response time. Control logic (22) also provides a learning function by modifying the stored profiles to accommodate changes in engine and accessory operation.

Abstract: A port having an advantageously small cross section portion for passing a sensor to a high pressure region and an adjacent relatively larger cross section threaded portion for coupling to the sensor. A sealing member being positioned adjacent the small cross section portion thereby reducing the force applied to the threaded portion.

Abstract: An Electronic Engine Controller (EEC) controls the operation of an electronically controlled throttle. The EEC generates a predicted desired throttle angle value as a function of upstream and downstream air pressure values, an air temperature value and a desired airflow value. A predicted actual throttle angle value is generated as a function of the upstream and downstream air pressure values, an air temperature value and an actual airflow value. A throttle angle difference value is generated as a function of the difference between the predicted desired throttle angle value and the predicted actual throttle angle value. A PID controller is employed to generate a throttle angle change value. The throttle angle change value is then added to the predicted desired throttle angle change value to generate a throttle angle control value, indicative of a position for said throttle. The throttle angle is then altered to a position corresponding to the throttle angle control value.

Abstract: In one embodiment of the present invention, a sensing system utilizing a capacitive sensor includes an integrator which is connected to the sensor and has an operational amplifier and an integrator capacitor, a reference voltage source, a clock generator generating a 3-phase clock, and a number of switches. The switches, during the first phase of the clock connect the sensor capacitors to the reference voltages and cause the capacitors to become charged, and connect the output and the input of the amplifier cand cause the integrator to be shorted. During the second phase, the switches connect the sensor capacitors contained in the capacitive sensor to the ground and disconnect the input of the integrator from the output of the integrator to cause the charges on the sensor capacitor to be transferred to the integrator capacitor.

Abstract: A method and apparatus for exciting a three-phase variable reluctance motor is used, for example, as an encoder system to commutate a rotor. The system includes a power source, a position sensor and excitation electronics. The position sensor is adapted to generate a plurality of variable induction values corresponding to relative motor torque rankings and absolute angular positions of the rotor. Excitation electronics is provided electric communication with the inductive sensor and the power source and is adapted to generate digital values of the inductance values corresponding to the motor torque rankings. Excitation electronics includes steering logic responsive to the digital values to generate an output signal having a value corresponding to the phase of the motor to apply current to so as to commutate the rotor.

Abstract: A method and system for generating an ignition coil output signal to control charging and discharging of a plurality of ignition coils in an internal combustion engine. A plurality of holding registers asynchronously receive a plurality of ignition coil data from a processor. The plurality of holding registers are memory-mapped and store the plurality of ignition coil data until subsequent ignition coil data is received from the processor. A sensor is provided for determining a position of the engine and generating a corresponding engine signal. A plurality of match registers are coupled to the plurality of holding registers for comparing the ignition coil data with a reference signal and generating an ignition coil output signal for receipt by one of the plurality of ignition coils based on the engine signal and the comparison between the ignition coil data and the reference signal.

Abstract: This invention teaches a series parallel heated oxygen sensor control wherein a parallel portion is used to apply heat to the oxygen sensor during warm-up and a series portion is used to apply heat to the oxygen sensor afterwards so that about one quarter of the amount of power is applied after warm-up.

Abstract: An electronic engine controller infers the instantaneous temperature of lubricating oil in an engine by determining a steady state oil temperature value as a function of engine speed and aircharge, determining an oil temperature time constant as a function of mass air flow rate and determining the instantaneous oil temperature as a function of the steady state oil temperature and the oil temperature time constant. The engine controller also determines an oil change interval as a function of the inferred oil temperature and the number of engine revolutions.

Abstract: A method and system for generating a position dependent output control signal. The position of a rotating machine, such as an internal combustion engine, is sensed and a corresponding position signal is generated. The position signal is processed to obtain the position dependent output control signal including a first control signal and a second control signal. The first control signal represents a sector of the rotating machine, and the second control signal represents the absolute position within the sector.

Abstract: A process and apparatus for monitoring catalyst conversion activity includes a predictor of feedgas emissions and a predictor of tailpipe emissions, each predictor providing an output for generating a ratio of conversion activity. Each predictor comprises a trained neural network receiving at least one of, and preferably a plurality of, the engine operating condition signals available from an electronic engine control. Preferably, each neural network is trained by inputting accumulated data acquired from performance evaluation of a plurality of vehicles having consistent powertrains but with different degrees of deterioration.

Abstract: This invention teaches operating a vehicle with a fixed throttle by determining a modified torque which is determined as a function of driver demand torque. Such modified torque is used to determine the amount spark retard or fuel cut-out required to achieve the demanded torque.

Abstract: A method and system for monitoring an evaporative purge system for malfunctions and leaks. First, a plurality of predetermined entry conditions are checked for satisfaction. If the plurality of predetermined entry conditions have been met, a flow of vapor in the evaporative purge system is determined. The evaporative purge system is then sealed from atmosphere so as to pull a vacuum on the fuel tank. The vacuum is compared to a predetermined vacuum range. If the vacuum is within the predetermined vacuum range, the vacuum is allowed to stabilize to obtain a stabilized vacuum level. A decrease in the stabilized vacuum level is determined after a predetermined amount of time to obtain a vacuum bleed-up. A vacuum bleed-up acceptance threshold is then determined based on the determined flow of vapor and the vacuum bleed-up is then compared to the vacuum bleed-up acceptance threshold.

Abstract: A method of inferring the temperature of a heated exhaust gas oxygen sensor is used in the control of the operation of an electronic engine control for an internal combustion engine.

Abstract: A method of controlling operation of a compressed natural gas vehicle as a function of a predetermined level of methane in the ambient. Vehicle ignition is turned off when a predetermined level of methane is sensed in the ambient.

Abstract: A micro-machined accelerometer includes a moveable metal plate, mounted upon a semiconductor substrate. The moveable metal plate includes an aperture which contains a pedestal and at least one torsion bar for connecting the pedestal to the moveable metal plate. Measurement electrodes formed on the semiconductor substrate combine with the metal plate to form measurement capacitors. A combined self-test/common electrode provides a dual function of a common electrode during operation of the accelerometer and a testing electrode during a self-test procedure.