03 ranger 3.0 miss under acceleration.

[nk321810]

hi.
my truck runs pretty well considering it has 185k. it has a rough idle, which may or may not contribute to this problem: it accelerates fine until it warms up, then if i step on it to pass someone or merge onto the interstate, it falls on its face somewhere between 3 and 4000 rpms. it does the same if i set the cruise on a 70 mph highway and encounter a hill. it seems to be getting worse. the plugs arent new, but i inspected all 6 and they look good. i also know they have around 20k highway miles on them. i tested the coil and found a bad post, so i replaced it with no change in the symptoms. i also just changed the fuel filter a couple days ago...no change there either. theres no engine light on, ive been thinking of unplugging a sensor just to turn it on so advance will scan the codes. so ive got a rough idle (which doesnt really bother me) and a hard stall under heavy acceleration when warm. any ideas?

thanks in advance...ive fixed more stuff with this forum than i ever have with a haynes manual!

 

[boominXplorer]

I would start with a compression check. On the 2001+ models the 3.0s have valve issues on higher mileage engines. My 01 ranger had this issue with 172k on it and my remedy was to put a v8 in it.

 

[LoneRanger89]

could be throttle postition sensor or could be coil pack, , could just need a tune up ..meaning plugs and wires , but those are just some of things it COULD be, it could be something else, If it its not any of those,, I got no idea

 

[Rawlz]

hi.
my truck runs pretty well considering it has 185k. it has a rough idle, which may or may not contribute to this problem: it accelerates fine until it warms up, then if i step on it to pass someone or merge onto the interstate, it falls on its face somewhere between 3 and 4000 rpms. it does the same if i set the cruise on a 70 mph highway and encounter a hill. it seems to be getting worse. the plugs arent new, but i inspected all 6 and they look good. i also know they have around 20k highway miles on them. i tested the coil and found a bad post, so i replaced it with no change in the symptoms. i also just changed the fuel filter a couple days ago...no change there either. theres no engine light on, ive been thinking of unplugging a sensor just to turn it on so advance will scan the codes. so ive got a rough idle (which doesnt really bother me) and a hard stall under heavy acceleration when warm. any ideas?

thanks in advance...ive fixed more stuff with this forum than i ever have with a haynes manual!

Check your IAC solenoid, it may have carbon buildup. I had a similar problem and that fixed it. BTW, my '03 Ranger 3.0l has 268,000 miles and I haven't had any major problems with it. Just upper control arms, as is typical for the Ranger.