Problem with a LR RANGE ROVER SPORT 2.7L TDV6

Engine management light on, fault code stored P0489 exhaust gas recirculation system. The fault was cured by using Forté Clean & Protect, 45 minute Forté Advanced Formula Motor Flush adding Forté Oil System Protector to the new oil, 2 x Forté Advanced Formula Diesel Treatment to the fuel tank and carrying out an extended road test.