Abstract: A compressor control system and method are provided for a vehicle air conditioner. The control device controls engagement of a compressor clutch member at engine start-up to discharge liquid refrigerant from the compressor. The control system provides for disengagement of the clutch member if the detected operating conditions are indicative of compressor lock-up without the use of a dedicated compressor lock-up sensor.

Abstract: A technique for determining the charge air temperature within an intake manifold of an internal combustion engine of a vehicle without using a dedicated temperature sensor. The technique includes identifying a non-linear dynamic model based on the physical concepts of thermal transfer and system identification technique. The charge air temperature model uses several available physical measurements from the vehicle, including inlet air temperature, engine coolant temperature, vehicle speed, manifold pressure, engine speed, exhaust gas recirculation condition, and the engine fan on/off state. The model parameters are determined based on specific vehicle characteristics, and collected data from the vehicle. The charge air temperature is predicted by the model at regular predetermined intervals from the physical measurements, the vehicle parameters and the charge air temperature from the previous time.

Abstract: A method of determining a vehicle battery temperature by a non-linear dynamic model based on the physical concepts of thermal transfer and a system identification technique. The battery temperature model uses several available physical measurements from the vehicle, including the engine coolant temperature, surrounding air temperature, vehicle speed and the engine fan on/off state. This method also includes the estimation of an initial value of battery temperature before starting the iteration process by the battery temperature prediction from the dynamic model.

Abstract: A system is provided for controlling the ratio of fuel to air in an internal combustion engine to protect the catalyst substrate of a catalytic convertor from thermal damage. The system comprises detecting a misfire rate and adjusting the amount of fuel within the system accordingly. More particularly, the detected misfire rate is compared to at least one predetermined misfire rate within the engine control unit. If the detected misfire rate is not equal to the predetermined rate, the ratio of fuel to air is changed a calibrated amount. Accordingly, when the misfire rate exceeds a predetermined rate, additional fuel is added to the system. By increasing the ratio of fuel to air, the oxidation reaction is reduced and the exothermic activity within the catalytic converter is lowered.

Abstract: A method of feedback control for an electronic fuel injection system in an internal combustion engine includes the steps of calculating a front O.sub.2 sensor switching voltage threshold based on a signal from a front O.sub.2 sensor upstream of a catalyst in an exhaust system for the engine and from a rear O.sub.2 sensor downstream of the catalyst, comparing a voltage output of the front O.sub.2 sensor to the calculated front O.sub.2 sensor switching voltage threshold to determine if a fuel/air ratio of the engine is rich or lean, and decreasing or increasing an amount of fuel to the engine by fuel injectors of the electronic fuel injection system if the fuel/air ratio is determined rich or lean, respectively.

Abstract: Many internal combustion engines have an auxiliary means for controlling airflow into the engine at idle, such as an Automatic Idle Speed (AIS) motor to compensate for changing load requirements. A method is disclosed for controlling the AIS motor and in turn engine idle speed to compensate for changing loads due to the operation of the air conditioner. The method recognizes the relationship between ambient temperature and pressures generated within the air conditioning compressor and the compensation necessary to maintain a smooth idle speed. The method also utilizes adaptive learning to relate a "looked up" of the air conditioner to the current value of auxiliary air flow required by a warmed up engine.

Abstract: A system and method for the detection and correction of purge corruption in the adaptive memory portion of a control system controlling, in part, the fuel to air ratio during the cold start up of an internal combustion engine. This is achieved by performing two calibrations (or updates) of the adaptive memory cells (or locations) during the previous engine operation. The adaptive memory is first updated with the purge system off. The memory locations addressed at this time are denoted as the purge free adaptive memory cells. Next, the adaptive memory is updated with the purge system on. These memory locations are denoted as the normal adaptive memory cells. During the next cold engine start, purge corruption of the adaptive memory is detected when the difference between the two calibrations exceeds a value representing an absence of purge corruption.