A control device is applied to an internal combustion engine equipped with an electric heating catalyst system provided with an EHC. The control device executes a preheating process to warm up an exhaust gas reduction catalyst prior to a start of the internal combustion engine by supplying electric power to the EHC, when the control device determines that a temperature of the exhaust gas reduction catalyst is lower than an activation temperature. The control device executes a determination process for determining whether water is adhered to a catalyst carrier. The control device starts the internal combustion engine without executing the preheating process when the control device determines by the determination process that water is adhered to the catalyst carrier, even when the control device determines that the temperature of the exhaust gas reduction catalyst is lower than the activation temperature.

Systems and methods for operating an engine that includes an exhaust tuning valve in its exhaust system are described. In one example, a position of the exhaust tuning valve may be adjusted to reduce a possibility of the exhaust tuning valve becoming stuck due to freezing water. In particular, the exhaust tuning valve may be cycled as ambient temperature approaches a temperature at which water freezes.

Selective catalytic reduction systems are known and are generally included in exhaust systems of diesel engines in order to treat the exhaust gases of such engines. Such systems involve the introduction of diesel exhaust fluid (DEF) into exhaust gas flowing in an exhaust passage of an engine. When dosing DEF onto a hydrolysis catalyst in a SCR system, the DEF will under certain conditions cool the hydrolysis catalyst sufficiently to either slow down or effectively prevent ammonia release, which creates a lag or delay in the function of the hydrolysis catalyst. This limits the amount of control which can be exerted over ammonia storage in the SCR catalyst, and NOx conversion. In a first step, a set of measurement data is received from one or more sensors provided in the system. Subsequently, a first set of characteristics associated with a state of a component of the catalytic system, a second set of characteristics associated with an output of the catalytic system and a third set of characteristics associated with a bias and a scaling factor in the system are derived. In a third step, the derived sets of characteristics are used to control the catalytic system.

An ECU executes a program including the steps of: determining whether an insulation resistance Ri is smaller than a threshold value Ri(0); if the insulation resistance Ri is smaller than the threshold value Ri(0), determining whether there is electric leakage between a vehicular body and an EHC and whether there is a possibility that there is electric leakage at a location other than a location between the vehicular body and the EHC; and if there is electric leakage between the vehicular body and the EHC, performing heating control.

Separation efficiency of a gas in a gas separator mounted on a vehicle is improved. The gas separation system mounted on the vehicle provided with an internal combustion engine includes the gas separator configured to separate a predetermined component in the gas under the existence of water, a first passage connected to the gas separator so as to introduce an atmosphere into the gas separator, and a second passage connecting between an exhaust passage of the internal combustion engine and the first passage so as to introduce exhaust gas of the internal combustion engine into the gas separator.

A control device comprises an estimated temperature calculation part calculating an estimated temperature of a conductive base based on an engine operating state, an electrical heating permission judgment part judging if to permit warmup of a catalyst device by electrical heating, and a catalyst warmup control part warming up the catalyst device by electrical heating when electrical heating is permitted and warming up the catalyst device by heat of exhaust discharged from the internal combustion engine when electrical heating is prohibited. The electrical heating permission judgment part prohibits warmup of the catalyst device by electrical heating when it is predicted that the actual temperature of the conductive base has diverged from the estimated temperature, when the estimated temperature is low in reliability, or when it is not possible to calculate the estimated temperature.

A diagnostic system (10) is provided and includes a sensor (24) disposed downstream from an exhaust gas aftertreatment system. Also included in the diagnostic system (10) is a central diagnostic unit (35) configured to diagnose a condensation condition associated with the sensor (24) for mitigating a sensor failure due to water condensation on the sensor (24), the central diagnostic unit (35) performing the diagnosis on the condensation condition based on water storage and release information related to a component of the exhaust gas aftertreatment system. The sensor (24) is activated based on the water storage and release information.

Systems and methods for operating an engine that includes an exhaust tuning valve in its exhaust system are described. In one example, a position of the exhaust tuning valve may be adjusted to reduce a possibility of the exhaust tuning valve becoming stuck due to freezing water. In particular, the exhaust tuning valve may be cycled as ambient temperature approaches a temperature at which water freezes.

An exhaust system includes a light-off catalyst, an exhaust system component, and at least one H.sub.2O trap. The exhaust system component is upstream from the light-off catalyst and includes catalyst material, the catalyst material configured to store hydrocarbons during a period when the light-off catalyst is warming up to a light-off temperature. The at least one H.sub.2O trap is at or upstream from the exhaust system component and is configured to perform H.sub.2O adsorption and desorption to increase a length of time for the exhaust system component to reach a hydrocarbon release temperature and prevent the exhaust system component from reaching the hydrocarbon release temperature prior to the light-off catalyst reaching the light-off temperature.

The disclosure relates to a method for determining the icing condition of a component of the exhaust-gas system of a motor vehicle that is not arranged directly in the exhaust-gas mass flow and/or of the feed line of the component. The method includes: determining a water quantity actually present in the component and in the feed line thereof and the state of aggregation of the water quantity; determining an energy quantity required for deicing and for volatilizing the water quantity; and determining an energy quantity supplied for deicing and for volatilizing the water quantity by radiated heat from components arranged directly in the exhaust-gas mass flow of the exhaust-gas system of the motor vehicle to the surroundings. The method also includes determining the icing condition of the component by comparing the energy quantity supplied for deicing and for volatilization with the energy quantity required for deicing and for volatilization.