Need help please, 2000 350 7.3 420000 just started acting like the valve cover gasket wires has a bad connection, changed gasket did not help .If you turn the key off and on several times it will go ahead and run fine,shut it off and may do it again ,repeat same thing with key it runs fine . Sounds all most like it is running out of fuel or just a few are firing. Need to do buzz test but do not have scanner,anyother way to tell if injectors are working.

 

Bad fuel pump relay? Or some other relay that makes a good connection after by cycled a few times?