it doesn't mean its gumed up'tolarences are very close in pumps and injectors lube helps out a bit, new parts are real tight somtimes to over come resistance the rack in the pump needs more prussure to move then over does it and goes to far the other way,producing the hunting effect,to the set rpms. power service is a conditioner for fuel, stops gelling,disapates water,lubes pumps and injectors,and cleans pumps and injectors. avalible at auto and walmart stores,alot of trucks and equipment pepole use it. even though its new it doesn't take much at assembly to get a piece of dust in there and thats all it takes as the parts are so tight. Back in the farm days we bught an IH 544 and the govenor would not even work the tractor just slowed right down under load, the IH guy came out and whacked the pump with a hamer and all was fine for years after. the tractor was new,just a piece of crap inside he said. I wouldn't wack the pump but i would try a little power service.