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iTrader: (19)

My father-in-law called me today and said his truck(see title) wouldnt crank. He keeps the fuel filter changed religously. Im a GM tech so im kinda in the dark on the Fords, dont have access to info. Since it was dark I havent done the normal checks. We sprayed a small bit of starting fluid in and it crunk up and shut back off. I just recently (1 month ago )replaced the water drain on the filter housing cause it was leaking bad . He called a mechanic from his work and he told him that there was a switch on the motor that he has replaced on the 7.3 before for this problem but he couldnt remember where or what it was. I dont remember seeing the security light on. Im gonna check the lift pump tomorrow to see if it has power. He also has replaced a starter type soleniod ,guessing for the glow plugs. It started great in the cold after that. Thanks in advance for the help !!

Leroy_454

Might the the CAM postion sensor. When you spin the engine over, look at the tachometer and see if it moves. If there is not movement the sensor is usually dead. Might not be it, but it is a common problem on 7.3L's.

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iTrader: (19)

Thanks Leroy. Does the cam sensor kill the fuel?

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iTrader: (19)

Well I started to check all the fuses cause I didnt hear the lift pump coming on. found where the fuel cut-off switch was and pressed it. It didnt feel to be sprung but it crunk up after that. Guess it had just poped up enough to kill the fuel. Thanks for the help !!

It'llrun

Late response, but... If the truck does this again and won't start just by pressing the button again, it may well be a bad CPS. I know sometimes the engine will run an then stall and restart soon afterward. Also, if it has an oil leak and gets below a certain point, this too will cause the engine to start very briefly and then stall.
When that happens, it simply will not continue to run na matter what you try.