An aftertreatment system includes an exhaust reductant tank configured to store an exhaust reductant. A filter is fluidically coupled to the exhaust reductant tank. The aftertreatment system includes a hydrocarbon detection device configured to indicate the presence of a hydrocarbon in the exhaust reductant. A catalyst is included in the system and configured to treat the exhaust reductant flowing through the system. The hydrocarbon detection device can include a hydrophobic paper, and can be disposed in the filter.

A method for monitoring a secondary airflow (SAIR) system in an engine includes determining degradation of the SAIR system adding a SAIR to downstream of an engine cylinder exhaust based on a comparison of the SAIR before and after a shutdown of a SAIR pump, the SAIR calculated from a fuel injection amount, an exhaust air-fuel ratio, and an engine intake airflow. In this way, SAIR at the exhaust manifold can be monitored utilizing existing onboard sensors and technology, thereby maintaining OBD and emissions monitoring, reducing engine emissions, and maintaining costs.

Methods and systems using model based and iterative calculations of mass flow throughout an internal combustion engine system. A secondary air injection valve is provided to selectively allow intake air to pass to the exhaust side of the engine system to aid in exothermic reaction with exhaust gasses exiting the engine for various purposes. The iterative calculations of mass flow include estimation of the mass flow through the secondary air injection valve.

A method for operating an exhaust gas burner that is situated in an exhaust gas system downstream from an internal combustion engine of a motor vehicle during a start phase of the exhaust gas burner, in which the internal combustion engine is not fired. The method includes an incremental increasing of the air mass flow supplied to the exhaust gas burner and an incremental varying of a fuel mass flow supplied to the exhaust gas burner.

An engine system includes an engine having piston-cylinder arrangements communicating with an intake manifold and an exhaust manifold, a turbocharger including a turbine in communication with the exhaust manifold and a compressor driven by the turbine and in communication with the intake manifold, and an EGR system including an EGR pump having an inlet side in communication with the exhaust manifold and an outlet side in communication with the intake manifold, and an EGR cooler that cools exhaust gas flowing through the EGR system. The engine system also includes a controller operably connected with the EGR pump and configured to selectively operate the EGR pump in a forward mode to flow exhaust gas therethrough in a first direction and in a reverse mode to substantially prevent flow of exhaust gas therethrough or provide a non-exhaust air flow therethrough in a second direction.

A particle filter assembly for a motor vehicle includes a particle filter, an exhaust-gas-conducting line which opens into the particle filter, and a secondary air supply. The secondary air supply is formed separately from the exhaust-gas-conducting line and fresh air is suppliable to the particle filter via the secondary air supply.

A method (200) for ascertaining an air volume provided by means of an electric air pump (134) in an exhaust system (120) of an internal combustion engine (110), including detecting at least one activation parameter (5) of the air pump and ascertaining (220) a provided air mass flow rate (8) on the basis of a calculation specification from the at least one activation parameter (5) by utilizing an inertia of the air pump (134) and/or an inertia of the air upstream and/or downstream from the air pump (134) and/or a differential pressure from upstream from the air pump to downstream from the air pump. In addition, a processing unit and a computer program for carrying out a method (200) of this type is provided.

A process for detecting reductant deposits includes accessing data indicative of signal output from a radiofrequency sensor positioned proximate a decomposition reactor tube; comparing the data indicative of signal output from the radiofrequency sensor to a deposit formation threshold; and activating a deposit mitigation process responsive to the data indicative of signal output from the radiofrequency sensor exceeding the deposit formation threshold.

In a method and device for controlling and/or monitoring the function of a secondary air supply in an emission control system of an internal combustion engine, the emission control system includes at least two catalytic converters situated in succession in an exhaust duct, it being possible for the second catalytic converter to be implemented as a combination of catalytic converter and particulate filter. For a secondary air diagnosis and for secondary air control, a two-point lambda probe is situated, with respect to a direction of flow of exhaust gas, downstream of the first catalytic converter. Measures are applied for compensating tolerance and aging effects of the two-point lambda probe. This results in particular in cost advantages in emission control systems for fulfilling stricter emission requirements. In particular, this makes it possible to operate the particulate filter in optimized fashion.

A method and control device for correcting an output signal of an exhaust gas sensor in an exhaust gas conduit of an internal combustion engine, a secondary air delivery system for delivering air into the exhaust gas conduit being associated with the exhaust gas conduit upstream from the exhaust gas sensor in the flow direction of the exhaust gas. During a measurement of the output signal of the exhaust gas sensor, air is delivered to the exhaust gas conduit via the secondary air delivery system during a correction phase by way of which a correction of the output signal of the exhaust gas sensor is derived. In this operating mode, a defined oxygen content exists in the gas mixture surrounding said sensor, so that the output signal can be compared with reference values.