Hey guys im new here but i really need some help i jus put a new intake manifold on my 79 400m and now when i turn it over it cranks slowly and has no spark until i let off the key and it sparks once i tried a different battery amd solenoid i checked the voltage at the coil and there is only 5 volts there are no broken wires and ive checked 3 grounds and nothing is helping could it be the ignition or anything else all feed back is helpful thanks