My engine had been running quite rough and I've had a lot of work done on it: Studs & bolts replaced on the exhaust manifold, valve looked at and the rocker arms had fallen off of 2 of them presumably due to cold starts. I live in Fairbanks, Alaska where winters are long and cold (down to -40). Also had the O2 sensors worked on and the oil switch replaced which took care of the oil light coming on and off. It runs much poorer in the cold.

The engine runs 1000% better now. But now a week later, I got a new engine code P0308-misfiring. I reset the codes by undoing the negative battery.

Is this something I should take care right away? I'm scheduled to take it back in next week due to this issue. It's probably been 3 or 4 years since I've had a tune-up. I don't drive very much. It's only got 97,000 miles 4wd, 4.7 engine.

Part of me wonders if this is the beginning of the end or maybe just a good time to bail on truck. The valves are worn and the rocker arms could come off again next winter when I forget or can't plug it in.

All the systems seem to have leaks. I had the power steering flushed in Jan and presumably they filled it. The latest mechanic notes leaks in the system. I checked it today and there was hardly any fluid in it. I think was oil leaking is really power steering fluid. So that needs immediate attention.

So is the misfiring issue, is that something I can wait and see if the code comes up again?