Thanks for all of the replys. I'll start with plugs and work up. It really begins to miss when I accelerate. It was all of a sudden. Just began to act up on Monday.

 

Thought I'd mention that the engine idles fine. Just when you speed up is when it begins to run poorly. Let off of the gas, and begins to run smooth again. The code that came up was PO300.

 

When you try to rev it up, does it sound like the engine is struggling at all? Does it run any hotter (temp wise?). Like I said before, a lot of guys on the forums have had issues with the catalytic converter getting clogged up, and causing the random/multiple cylinder misfire. But, on the surface, everything else checks out like plugs, wires, cap, rotor, coil, etc.

As an outside shot, you can undo the 2 bolts on each exhaust manifold, and just let the pipes kinda hang loose, and try to see if it runs smooth all the way through the RPM's. Thats what I eventually ended up doing to validate my theory on the CAT.

Especially since you say it idles fine (not a lot of exhaust gasses trying to go through the pipes). If not that, the other common thing to look at is fuel pressure/fuel pump issues. The good news is on our RAM's the fuel pump/filter is in the tank, so you get to buy a complete unit if its deemed to be the root cause. good luck man!

 

I had an old f-150 that idled fine but you couldn't rev up, solved problem with a new fuel filter. Parts chaser is right though. I don't think you can replace just the filter. I think they list it as a whole pump assembly.

 

Nope you can't it's a complete assy I know I had to replace mine

 

Very familiar with the fuel pump--had to replace it about 3 years ago--when the tank was 3/4 full. The temp gauge is showing that the engine is not over-heating--replaced the thermostat last year. Will check the CAT, though.