Help needed PLEASE!!!
I'm not a mechanic professionally but I can fix pretty much anything that goes wrong with my truck so I guess in other words I know my way around an engine. I have a 1991 f150 with a 4.9 straight 6 in it. I recently bought it knowing it needing some work so I wasn't surprised to find it had more problems that originally expected. My problem is that when cranking an driving the engine shakes an sputters violently and it has trouble cranking when cold. I have replaced the fuel pump, filter, relays and fuel pressure regulator... The plugs and wires and the ignition coil, the alternator and radiator. I am at a complete loss. I've done everything short of replacing the fuel rail and injectors. After driving about half a mile the sputtering will let up a little but it will still sputter with hard acceleration. It feels like while driving that the fuel lines have air in the system. That's just a guess however.
I appreciate any help you can give me
Thanks







