Abstract: A method of monitoring hydrocarbons concentration in an exhaust gas includes the steps of: sampling exhaust gas on a vehicle, isolating the hydrocarbons from the exhaust gas on a vehicle, and measuring the amount of hydrocarbons isolated from the sample on a vehicle and providing an indication based on the amount of hydrocarbons. A sensor assembly for monitoring the concentration of hydrocarbons in an exhaust gas of a vehicle includes: a hydrocarbon absorbing material placed in a stream of gas on a vehicle, a gas sensor operatively connected with the absorbing material and in the stream of gas and producing a gas signal, and a sensor controller connected to the gas sensor for receiving the gas signal and for determining the amount of hydrocarbons.

Abstract: Methods and apparatus are provided for monitoring the performance of a hydrocarbon trapping device which removes hydrocarbons from an engine exhaust stream during cold startup conditions before the catalyst has reached its light-off temperature. The electronic engine controller which provides conventional fuel control functions is used to numerically integrate sensed values during a predetermined time interval in the engine's startup period. The sensed values indicate the rate at which hydrocarbons are being retained or purged by the trap, and the result of the integration indicates the total amount of hydrocarbon molecules trapped or purged. The integration result values may be retained for future readout during diagnostic procedures, and the result values may be compared with a threshold value to generate an alarm indication whenever the integration result value indicates that the trap is not performing satisfactorily.

Abstract: This invention is directed to an electrically heatable catalyst device comprising an electrically insulating substrate carrying an electrically conductive material selected from metal oxides, carbides, nitrides and silicides, and applied thereon a washcoat carrying a catalyst.

Abstract: This invention is directed to a system for monitoring the efficiency of a catalyst employed to convert exhaust gases containing carbon monoxide, hydrocarbons and nitrogen oxides, e.g., those generated by an internal combustion engine such as in an automobile. The system comprises a thin-film resistive device and an electrical circuit connected to said thin-film resistive device capable of determining a change in the electrical resistance of a electrically conductive material provided in the device, the electrical resistance being subject to change during conversion of said exhaust gases over the catalyst.

Abstract: An automotive internal combustion engine is equipped with a hydrocarbon adsorber for the purpose of controlling the emissions of unburned hydrocarbons from the vehicle's tailpipe. Regeneration of the adsorber is achieved by an electronic engine controller operating an air pump and a sample pump, using information from an exhaust gas oxygen sensor.

Abstract: An automotive engine and exhaust aftertreatment system includes an engine, a catalytic exhaust aftertreatment device for receiving exhaust gas from the engine, and an air source for supplying air to the exhaust stream entering the catalyst. An exhaust gas oxygen sensor determines the amount of oxygen contained in the exhaust entering the catalyst, and an engine control computer connected with the air source and with the oxygen sensor monitors the amount of oxygen contained in the exhaust and controls the amount of air supplied to the exhaust stream by the air source such that the available oxygen is slightly in excess of the stoichiometric requirement. In this manner, the light-off time of the catalyst is minimized.

Abstract: An automotive internal combustion engine is equipped with a hydrocarbon adsorber for the purpose of controlling the emission of unburned hydrocarbons from the vehicle's tailpipe. Regeneration of the adsorber is achieved by an electronic engine controller operating a purge air system for drawing desorbed hydrocarbon material into the engine's intake.

Abstract: An automotive internal combustion engine is equipped with a hydrocarbon adsorber for the purpose of controlling the emissions of unburned hydrocarbons from the vehicle's tailpipe. Regeneration of the adsorber is achieved by an electronic engine controller operating an air pump with information from an exhaust gas oxygen sensor.

Abstract: An automotive internal combustion engine is equipped with a hydrocarbon adsorber for the purpose of controlling the emissions of unburned hydrocarbons from the vehicle's tailpipe. Regeneration of the adsorber is achieved by an electronic engine controller operating an air pump and a sample pump, using information from an exhaust gas oxygen sensor.