an excellent question -
I don't know what I want to know. <g> I am interested in checking things that, to my non-Ford diesel mind, seem like they may be related to the symptoms I'm experiencing with my truck.
It sort of 'surges' at certain speeds. As though I were pushing and releasing the throttle pedal slightly and repeatedly - but it happens with my foot rock steady.
So far I changed the engine oil and filter. Although I forgot to do my usual 'pre-change 'flush' - normally I add a quart of so of Marvel Mystery Oil a few hundred miles before I chnage the oil. I changed the transmission fluid and filter. And I changed the screw-on fuel filter.
Not too long ago I also replaced the FIPL sensor too. Although that 'weird shifting up and down' problem seems to be gone now.
Although: what the hell do I know? Maybe the transmission just does something Else weird now. <g>
So anyway: while I wait for the ******* to either quit or have something fall out the bottom - I thought I may as well check a few things. Like the fuel pressure. <g>
PHM
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What pressure do you want..... The inlet to the filter or the outlet to the injection pump. A new filter will have a small amount of restriction but. You really need to tell us what pressure you want... I'm thinking you want the outlet pressure more than the inlet pressure.... Both would be nice to have but. If I only had one it would be the injection pump inlet pressure. These 7.3 fuel systems have a vacuum switch on the fuel outlet to the injection pump. It lites up a dash pic that tells you the filter is plugged up and that the injection pump is drawing more fuel than can be pushed thru the filter.... I saw my dash lite come on a few times way back in 1997 about a year after I got my truck..... Took me a whiles before I figured out what was going on..... Changed the filter and its been fine for years.... But I have changed the filter, pump, injection pump and many other fuel related things since then....
