So my '96 stock cummins has been missing power especially towing and uphills, so I figured a simple fix might be replacing the overflow valve. But when I took it out, I noticed it had nothing inside...no ball, no spring, just empty? I've read there are several different oem versions of these valves, but does that sound right at all? Was the prior owner compensating for a weak lift pump by somehow getting rid of the spring and ball that creates pressure? I replaced with an aftermarket one, now the truck won't start...can't get fuel out of cracked injectors and weak out of fuel filter bleed screw. Was putting in the aftermarket enough to finish off the lift pump???