Exhaust Gas Recirculation (EGR) works by recirculating a portion (15%) of exhaust gas back through the engine.
The exhaust gases can build up over time in the valve and can become clogged with carbon deposits that can prevent the valve from opening and closing properly. Sensors can be damaged and water coolers can also burst.
Turning off the EGR is fantastic for your engine. Once off, the engine will draw 100% clean atmospheric air instead of recycled air from the exhaust. Engines run cleaner and cooler due to atmospheric air temperature being less than exhaust gas. Blanking plates can be added to remove the value & cooler.
EGR valve can be expensive to replace if it becomes damaged. It can be removed from software including fault codes & cycle maps.