Code P0404 fix???

P0404 Code code p0404 The vehicle lacks of power When I clear the p0404 fault code, the vehicle runs great for a couple of days or miles (costumer mentioned that code p404 P0404 Exhaust Gas Recirculation Circuit RangePerformance EGR Valve

code p0404 Failure code of P0404 had been recorded I removed the EGR valve and discovered that small pieces of carbon had logded the valve open