Re: how does a glow plug relay work
You might want to check and see if the new relay that you bought is a case isolated or not. There is a difference between a starter relay and a glow plug relay in that usually the starter relay only needs one hot wire and no ground where the gpr needs the hot wire and the signal wire from the pcm
for the ground. Also make sure that your batteries are fully charged as this will cause problems if you have been cranking on the starter and have drained them down.
96 F250 XLT 4x4, 4:10 gears, 5 speed, Tymar intake and HX hose, downpipe, pyro and boost guages, coolant filter, Luc clutch