Wait to start light,glow plug warm up

 

Not too sure. I was told to put my hand on the bottom of the fuel tank and have someone turn the key to ON to feel for a vibration but others are saying to look for an inline (mounted to the frame). I guess I'm unclear where the fuel pump relay is and where the actual pump is located.

 

Got it. Thanks. Is the fuel pump relay triggered AFTER that light goes out or should it send power as soon as the key goes to ON?

 

There were two setups, first was after,second was with key on,not sure on years,the latter was to assist injector pump quicker,less wear,so no pump in tank,just guage and sock

 

And the oil pressure sensor is in series too,so check for power at lift pump with it disconnected,power? You gotta test a couple of ways,after wts light, maybe engine cranking?,no power, check oil pressure sensor

 

Any guess on where the oil pressure sensor is? Also, does spinning the engine over generate enough pressure to activate the switch or does the engine actually have to crank and start to generate enough pressure? This would potentially help me understand if the issue is the relay or the pump correct?

 

Good question,it's by oil filter on block?it's been a while,ill look in book

 

You gotta understand,I'm in road salt country,we see a 6.2,and we flock to it,look at that historic truck!so relay on firewall,gray wire,feed to pump,that is energized with glow plug relay and crank,oil pressure sensor (sending unit)takes over after release from crank