Help ! I have a 1993 460 f-350 That I picked up at an auction so I dont really no the history on it . It starts right up and sounds good for about a minute and then dies slowly like it running out of fuel or loading up. I can keep it running by feathering the throttle . I thought it might be the cat so I gutted it with no change . I ran the codes and only came up with improper temp code . Next I ran fuel pressure test and it was moving up and down between 10 and 32 as the pump cycled with the engine off I guess my question is there a check valve or is the pressue regulator supposed to keep the pressure from fluctuating . I dont want to replace the fuel pump and have it be something simple .

Thanks Jeff

 

Hi jtb5616 and welcome to FTE

The fuel pressure should sit between 30 and 45 psi and not drop moe than about ummm 5 psi in a couple minutes. I would suspect that your fuel pressure regulator is shot. Does it do it on both tanks? When it is running what does the fuel pressure do as the engine dies?
If only on one tank it's possible to have a pump problem but I'd still suspect the FPR first.

 

Hi jtb5616 and welcome to FTE

The fuel pressure should sit between 30 and 45 psi and not drop moe than about ummm 5 psi in a couple minutes. I would suspect that your fuel pressure regulator is shot. Does it do it on both tanks? When it is running what does the fuel pressure do as the engine dies?
If only on one tank it's possbile to have a pump problem but I'd still suspect the FPR first.