Engines made after January 1, 2010 may be equipped with which exhaust aftertreatment system?

Engines made after January 1, 2010 may be equipped with which exhaust aftertreatment system?

• A. Diesel Particulate Filter
• B. Selective Catalyst Reductant
• C. Turbocharger
• D. Oxygen Sensor

Answer: (B)

High-efficiency exhaust NOx control became essential as emissions standards tightened after 2010, and selective catalyst reduction is the system designed to do that directly in the exhaust stream. It injects a reductant, typically urea-based DEF, into the exhaust and passes the mix over a catalyst, turning NOx into nitrogen and water. This approach specifically targets NOx emissions, which were a major focus of newer diesel requirements, so engines from that era are commonly equipped with SCR to meet those limits. Diesel Particulate Filters also live in the exhaust aftertreatment train, but their main job is to trap soot particles rather than chemically reduce NOx. An Oxygen Sensor is a monitoring device used by the engine control system, and a Turbocharger is part of the intake side that boosts air, not aftertreatment.

High-efficiency exhaust NOx control became essential as emissions standards tightened after 2010, and selective catalyst reduction is the system designed to do that directly in the exhaust stream. It injects a reductant, typically urea-based DEF, into the exhaust and passes the mix over a catalyst, turning NOx into nitrogen and water. This approach specifically targets NOx emissions, which were a major focus of newer diesel requirements, so engines from that era are commonly equipped with SCR to meet those limits. Diesel Particulate Filters also live in the exhaust aftertreatment train, but their main job is to trap soot particles rather than chemically reduce NOx. An Oxygen Sensor is a monitoring device used by the engine control system, and a Turbocharger is part of the intake side that boosts air, not aftertreatment.