problems with 99 3500
 

truck wouldnt start wasnt gettin fuel to th inj pump, replaced lift pump with holley blue, wouldnt come on with key so wired it straight, now if it sits it will bleed off or somthing its real hard starting but if u run it and then shut it off it starts right back, it needs a throttle position sensor but wats causing it not to start right ,any help

unwire it from the "straight" that you spoke of. the truck needs little to no fuel pressure at startup to get going. excess fuel pressure causes hard starting. you should get a quick bump of fuel and then once you stop cranking it should run up to operating pressure. there could be other issues, but start there.

leave your fuel cap loose, likely the hard start will stop, excess tank vacuum will draw the fuel from the IP back to the tank, thus it takes more cranking to get the truck to start