An exhaust gas aftertreatment system for an internal combustion engine charged by an exhaust gas turbocharger and spark-ignited by means of spark plugs has a particulate filter and a first three-way catalytic converter downstream from the particulate filter in a position close to the engine in an exhaust gas system connected to an outlet of the internal combustion engine and another three-way catalytic converter arranged in the underbody position of the motor vehicle, downstream from the first three-way catalytic converter. An exhaust gas burner is active from the start of the engine, introducing hot exhaust gas into the exhaust gas system downstream from the particulate filter, in order to heat at least one of the three-way catalytic converts to a light-off temperature, as quickly as possible after the cold start, thereby allowing an efficient exhaust gas aftertreatment. The exhaust gas burner can be switched off when at least one of the two three-way catalytic converters has reached its light-off temperature.

A fuel injector for an exhaust heater includes a cover and an air blast nozzle. The cover has a nozzle seat, a fuel inlet, and an air inlet, the nozzle seat arranged along a flow axis. The air blast nozzle is seated in the nozzle seat and has a unibody. The air blast nozzle unibody is in fluid communication with the fuel inlet and the air inlet arranged along the flow axis to port fuel and air into a combustion volume, e.g., to heat a stream of exhaust gas flowing between an engine and a catalytic reactor by combustion with fuel introduced through the fuel inlet and air introduced through the air inlet.

A heating device for an exhaust system of an internal combustion engine and having: a tubular body, where a combustion chamber is obtained on the inside; a fuel injector, which injects fuel into the combustion chamber; at least one inlet opening, which can be connected to a fan so as to receive an air flow, which is directed to the combustion chamber and gets mixed with the fuel; a feeding channel, which receives air from the inlet opening, surrounds an end portion of the fuel injector and ends with a nozzle, which is arranged around an injection point of the fuel injector; and a spark plug, which is mounted through a side wall of the tubular body so as to trigger the combustion of a mixture of air and fuel. The fuel injector is configured to spray at least 80% of the fuel against an inner surface of the feeding channel.

When a temperature increasing process is performed, a CPU sets a target temperature of a catalyst to be lower when a coolant temperature is low than when the coolant temperature is high. The CPU decreases an increase coefficient of fuel in the temperature increasing process when a value obtained by subtracting an estimated value of a temperature of the catalyst from the target temperature is equal to or less than a first prescribed value.

A method for operating an exhaust-gas burner (B) of a vehicle (100) which has at least an internal combustion engine (V) and a catalytic converter (C1, C2), wherein exhaust gases (22, 24) of the exhaust-gas burner (B) are merged, upstream of the catalytic converter (C1, C2), with exhaust gases (12) of the internal combustion engine (V), forming an exhaust-gas mixture, wherein a lambda value of the exhaust gases (22, 24) of the exhaust-gas burner (B) is set in a manner dependent on a lambda value of the exhaust gases (12) of the internal combustion engine (V).

A vehicle control system includes: a fuel control module configured to control gasoline fueling of an engine in open loop based on a target engine lambda; and a burner control module configured to control gasoline fueling of a burner based on (a) a target lambda input to a three-way catalyst (TWC) in an exhaust system of the engine and (b) a lambda of exhaust input to the TWC. The burner is coupled to the exhaust system between (a) an output of the engine and (b) an input to the TWC.

A variety of methods and arrangements for controlling the exhaust gas temperature of a lean burn, skip fire controlled internal combustion engine are described. In one aspect, an engine controller includes an aftertreatment system monitor and a firing timing determination unit. The aftertreatment monitor obtains data relating to a temperature of one or more aftertreatment elements, such as a catalytic converter. Based at least partly on this data, the firing timing determination unit generates a firing sequence for operating the engine in a skip fire manner such that the temperature of the aftertreatment element is controlled within its effective operating range.

A method (200) for determining an amount of hydrocarbons in an exhaust gas (10) downstream of a lean-operation internal-combustion engine (110), comprising the following steps: observing a first catalyst heating mode of the internal-combustion engine (110) at a high catalyst temperature, wherein a predefinable amount of fuel having a predominantly non-combusting portion is introduced into a combustion chamber of the internal-combustion engine (110); determining an actual temperature change downstream of an oxidation catalyst (120) downstream of the internal-combustion engine (110) during the first catalyst heating mode; and determining the amount of hydrocarbons (cHC) in the exhaust gas (10) upstream of the oxidation catalyst (120) based on the actual temperature change. Furthermore, a computing unit (140) and a computer program for carrying out such a method (200) are proposed.

A method for operating a hybrid motor vehicle. In one example, the vehicle comprises an internal combustion engine (10) and at least one electric motor (20). As long as at least one parameter of an exhaust gas aftertreatment system (12) of the internal combustion engine (10) lies outside a given range, the starting of the internal combustion engine (10) is delayed and the internal combustion engine (10) is dragged by the electric motor (20). At the same time at least one measure is carried out which changes the parameter.

A system includes: an engine; and an aftertreatment system for treating exhaust gas produced by the engine, the aftertreatment system including: an exhaust conduit configured to receive the exhaust gas and hydrocarbons from the engine; a preheating oxidation catalyst; a primary oxidation catalyst disposed downstream of the preheating oxidation catalyst; a selective catalytic reduction system disposed in the exhaust conduit downstream of the primary oxidation catalyst. The aftertreatment system includes: a controller configured to: determine a temperature of the exhaust gas at an inlet of the selective catalytic reduction system, and in response to the temperature of the exhaust gas at the inlet of the selective catalytic reduction system being below a threshold temperature, cause the engine to provide the hydrocarbons to the exhaust conduit. The preheating oxidation catalyst is configured to catalyze combustion of the hydrocarbons so as to increase the temperature of the exhaust gas to above the threshold temperature.