What is an exhaust gas recirculation system and how does it work?

What is an exhaust gas recirculation system and how does it work?

The EGR system works by returning a small portion of exhaust gas to the engine’s combustion chambers through the intake manifold, lowering combustion temperatures and therefore reducing the amount of NOx emitted. The EGR valve is the main component of the EGR system and it’s normally closed.

What are the types of exhaust gas recirculation system?

Depending on whether the exhaust gas is recirculated before or after the turbocharger, there are two types of EGR systems:

• High pressure EGR.
• Low pressure EGR.

  What is an exhaust gas recirculation system designed to reduce?

  The engine EGR system is designed to reduce the amount of oxides of Nitrogen produced by the engine during operating periods that usually result in high combustion temperatures. NOx is formed in high concentrations whenever combustion temperatures nearing adiabatic flame temperature.

  What are the types of exhaust gas recirculation?

  There are two types of EGR: internal exhaust gas recirculation (iEGR): the exhaust gases are sucked back in the cylinder by overlapping the opening… external exhaust gas recirculation EGR: exhaust gases are recirculated back into the intake manifold by using and…

  How does an EGR work?

  EGR works by recirculating a portion of an engine’s exhaust gas back to the engine cylinders . This dilutes the O 2 in the incoming air stream and provides gases inert to combustion to act as absorbents of combustion heat to reduce peak in-cylinder temperatures.

  Where is the EGR sensor located?

  The EGR pressure sensor is located within inches of the EGR valve. The exact location varies depending on the engine (2.5L, 3.0L or 4.0L). It is usually attached to the upper intake manifold with two small bolts.

  What are the functions of the EGR valve?

  The function of the EGR valve is to recirculate small amounts of exhaust back into the combustion chambers of the engine in order to decrease the combustion temperature, thereby reducing the formation of smog-producing nitrogen oxides. EGR valves can malfunction by becoming stuck open or closed due to carbon buildup.