A recycling loop configuration of an exhaust gas aftertreatment system decreases a level of system-out NO.sub.x emissions of an engine. An apparatus including the configuration has an exhaust gas recycling system having a closed gas recycling loop system configured to heat gas circulating within the loop, and a blower for circulating gas within the loop. A method for operating the engine includes preheating at least one aftertreatment component of an exhaust gas aftertreatment system of the engine by exposing the component to heated gas circulating in a closed gas recycling loop.

A recycling loop configuration of an exhaust gas aftertreatment system decreases a level of system-out NO.sub.x emissions of an engine. An apparatus including the configuration has an exhaust gas recycling system having a closed gas recycling loop system configured to heat gas circulating within the loop, and a blower for circulating gas within the loop. A method for operating the engine includes preheating at least one aftertreatment component of an exhaust gas aftertreatment system of the engine by exposing the component to heated gas circulating in a closed gas recycling loop.

An exhaust system includes an exhaust pressure sensing system having sensor conduits structured to fluidly connect to an exhaust conduit in an exhaust system and feed exhaust to a differential pressure sensor. The differential pressure sensor produces a pressure signal indicative of a pressure drop across an exhaust aftertreatment element such as an exhaust filter. A plugging-mitigation conduit provides an always-open leakage path to convey condensate in a stream of leaked exhaust between the sensor conduits to prevent formation of deposits that can impact pressure sensing accuracy.

An exhaust system includes an exhaust pressure sensing system having sensor conduits structured to fluidly connect to an exhaust conduit in an exhaust system and feed exhaust to a differential pressure sensor. The differential pressure sensor produces a pressure signal indicative of a pressure drop across an exhaust aftertreatment element such as an exhaust filter. A plugging-mitigation conduit provides an always-open leakage path to convey condensate in a stream of leaked exhaust between the sensor conduits to prevent formation of deposits that can impact pressure sensing accuracy.

An exhaust tailpipe/emissions filter employs a reusable/replaceable insert and is configured to slide into and/or onto the exhaust tailpipe of the automobile to reduce air pollution.

An inline reductant filter assembly includes a filter housing, a filter media, and one or more valves. The filter housing is fluidly coupled to an upstream portion of a reductant line and a downstream portion of the reductant line. The filter media is positioned in the filter housing. The one or more valves are selectively movable from a first position to a second position. In the first position, the one or more valves permit fluid to flow along a first fluid flow path from the upstream portion of the reductant line, through the filter media, to the downstream portion of the reductant line. In the second position, the one or more valves prevent fluid from flowing along the first fluid flow path through the filter media.

An exhaust tailpipe/emissions filter employs a reusable/replaceable insert and is configured to slide into and/or onto the exhaust tailpipe of an automobile to reduce air pollution.

An exhaust tailpipe/emissions filter employs a reusable/replaceable insert and is configured to slide into and/or onto the exhaust tailpipe of the automobile to reduce air pollution.

Methods and systems are provided for an emission control device that includes a particulate filter with a bypass. In one example, a method includes bypassing the particulate filter when the exhaust gas has a decreased soot load and when the particulate filter has a decreased soot storage. The method further includes reducing the filter bypass flow and terminating or adjusting a deceleration fuel shut-off operation due to an exhaust temperature proximate to the particulate filter being above a threshold.

Methods and systems are provided for an emission control device that includes a particulate filter with a bypass. In one example, a method includes bypassing the particulate filter when the exhaust gas has a decreased soot load and when the particulate filter has a decreased soot storage. The method further includes reducing the filter bypass flow and terminating or adjusting a deceleration fuel shut-off operation due to an exhaust temperature proximate to the particulate filter being above a threshold.