Fuel pump works with hot wire but not with ing key. Even then the motor will not get gas into cyl. Can put gas in air cleaner and it will start for a few seconds. Replaced fuel pump/filter and relay. Still won't run. What can it be??
mdk68gto, ase certified m tech
Favorite Answer
that could be a few different things. on a gm vehicle the computer has to see a tech Reference signal of at least 400 rpm, if the computer does not see that the pump will not be energized. when the computer does see this Reference it sends a signal to the relay that controls the fuel pump not directly to the pump. i would look fro that signal wire and see what you have there. as someone else mentioned the computer could be the source of the problem.
Anonymous
bleed the air out of the rail where you attach the fuel pressure guage, keep it open and turn key on and off until fuel comes out.
Lynn B
bad module in distributor or no ecm pulse/coil pack module not sure what your motor is.