Occasional misfire/cutout

The combination of lower engine speed (below 1.8k or so) and throttle mostly open, including normal acceleration immediately after up shift. Split second mis-fire a couple few times random intervals until engine speed gets up a bit. I can be a bit less aggressive on the throttle and it happens less. I realize it is not in its power-band but these cut-outs still are not good. If its a long grade I will gear down and keep the RPMs up a bit and its fine. This symptom is usually on-ramps or pulling away form stop lights. 285k on this 3.4 and I still consistently get 20-22 MPG. Starts and runs great otherwise. This seems more like an ignition issue and not really a fuel delivery issue. This engine has that dual/redundant spark system so I guess that means there are only 3 coil packs to deal with...which is my hunch ATM

 

Do you have a scan tool?

How old are the plug wires?

What I am hoping for is that you do have a scan tool and that it and the PCM are sophisticated to show live data misfires and/or pending codes. Like you mentioned 3 coils... if the misfires are on a shared coil, swap coils and retest.

 

Yes, a simple one
Possibly original.


Both good leads (No pun intended)

 

Without any codes either hard or pending this turns into an exprience game. Do you put a set on new plugs and wires on it "just because" or ?
Pop your scanner in and see what you can discover of its features, you never know what you will find.