HI ZONIE77, read your response to the hard starting when engine is hot, if fuel is draining back to the tank, then why is cold starting not a problem. and if the fuel pump is at fault how about a fuel pressure check valve added to the fuel line before the filter ,the check valve would let fuel enter the sys ,and not drain back to the tank.[ a one way check] just a thought, not sure if this would cause a problem with too much pressure build up and no way to return excess pressureback to the tank? this check valve sys is used on detroit diesels equipted with external gear meshed regulated fuel pumps . this check valve may by pass an important function of the tank mounted fuel pump.do you know if there isa check valve integral to the pump to hold fuel at the injectors .thanks brooklyn tony