Im stumped, It's missing and ticking.

Try touching a long rod or screwdriver or mechanic's stethescope if you have one to the top of the fuel pump while it is running and see what you hear. I have seen pump arms break where they pull on the diaphragm causing noises and loss of fuel pressure.... Did you check fuel pressure? Also.. did you happen to get fuel anytime close to when this occured? If the tanker was there anytime soon you have probably picked up water and who knows what else in your fuel system.

BD