It sounds like you have a valve that is not sealing or have a scuffed piston or cylinder. Start by getting a quality compression gauge and doing a compression check on all 8 cylinders with the engine as hot as possible and the throttle wide open. Drive it for a while to get the coolant and oil temperatures as hot as possible. Disconnect the crank and cam sensors prior to cranking the engine for the compression test. The crank sensor is on the passenger side rear bottom of the engine block just above the oil pan rail. The cam sensor in on the bottom of the passenger side front cylinder head.rdesai said:So I got my 4.7 rebuilt, turned out I had a small leak in my head gasket. but now I have a new problem.
I have a misfire in cylinder #1 that started right after I started driving it again. It lasted about a week then it turned in to a random cylinder misfire.
It turned out to be a bad computer. So I replaced it and I ran fine for about 2 weeks.
But couple of days ago it came back. I get a code of P0307, but it feels like its multiple cylinders.
I replaced to injectors, coils and sparkplugs when it was rebuilt.
When I accelerate it runs great, its worst at idle and when im holding a constant speed. the whole truck shakes when at this point feels like I'm on a dirt road.
Any one got any ideas?