The term refers to the removal of the Exhaust Gas Recirculation system from an engine. This system is designed to reduce nitrogen oxide (NOx) emissions by recirculating a portion of the engine’s exhaust gas back into the intake manifold. This dilution of the intake charge lowers peak combustion temperatures, thereby inhibiting NOx formation. The removal process typically involves physically blocking off the EGR valve and cooler, and often requires reprogramming the engine control unit (ECU) to prevent error codes and optimize engine performance in the absence of the EGR system.
The motivation behind this modification often stems from the belief that it can improve engine performance and fuel economy. Proponents suggest that eliminating the recirculation of exhaust gas results in a cleaner intake charge, leading to more efficient combustion and increased power output. Furthermore, some individuals opt for this modification to prevent the build-up of carbon deposits in the intake manifold, which can occur due to the introduction of exhaust gas. Historically, such modifications were more common in older diesel engines, but the practice has extended to gasoline engines as well. However, it is crucial to note that removing this system can have negative environmental consequences due to increased NOx emissions.
