2000 Ranger. 2.5L 4 banger. She's bucking / missing on cylinders when warmed up, at cruising speed when under light or moderate acceleration. MAF is about a year old. Coil packs, plugs and wires, closer to 2. Thoughts? With the age of the truck and the lack of free time I have, Kinda prefer to just do a 'shotgun approach'. Basically just toss whatever needed to get it solved. If that means replacing 3-4 things when only 1 thing was needed, its ok. With the age of the truck, replacing stuff isnt a bad idea anyway. It also ocassionally has a surging idle and also is slow to return to normal idle speed after letting off the throttle. Usually takes 30 seconds or so to drop below 2000 rpm and go back down to a normal idle speed. Thoughts?

 

Clean the MAF sensor, dirty MAF causes bucking, new or not

2000 2.5l has dual spark plugs and engine can run fine on only 4, extra 4 add power, same engine ran on 4 spark plugs from 1974 thru 1988
Warm up engine, shut it off, you can do it with cold engine as well but engine may stall
Unplug either coil pack's 3 wire connector, to disable it
Start engine
Should run smooth with slightly lower idle, but no misfires, if there is a miss then there is a problem with spark plugs/wires or coil pack on working side
Shut off engine, and plug coil pack back in and unplug the other one, same test
You should do this test once a year to make sure all spark plugs are working

Try a can of injector cleaner in the gas tank, like Seafoam
I do this once a year and do notice smoother idle on my 1994 4.0l after its run thru the engine, so could probably do it every 6 months but I am cheap, lol

 

It idles fine, its just doing it at cruising speed under light to moderate acceleration but will try yanking 1 coil pack plug, and then alternate to see if that tells me which side its on. Also, have some SeaFoam, wil give that a go. Did clean the MAF, no change