1994 300K on motor 100K + on pump drove the truck yesterday it happened to stall twice which has never happened but I did notice it was ideling low-600 rpm's I have been getting some surging but all in all it runs great but today no-start doesn't even sound like she wants to start. New starter new batteries spining plenty fast, glow plugs have been working fine lift pump working fine , return lines maybe 3 years ago all new injectors maybe 5 years ago but nothing I even hit it with starting fluid nothing. It has been starting harder lately but always started. Can the pump be just worn out Any other ideas?