i bought this ranger about a month ago and everything i have done still dont fix the prob, it will idle fine then about 5mins or so the idle drops and misses and runs rough but if i hit the gas it dont have a miss at all and runs smooth until i let off the gas again. Ive changed spark plugs, wires idle air control sensor, what next the egr? there is no vacume leaks either i already checked im just stomped by what it could be.

check the IAC valve (idle air control)

it may be stuck....try taking it off and spraying it down with some carb cleaner

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1996 XLT 2.3T "White Lightning" 5/7 dropped, Turbo street toy
2006 FX4 Off Road, DD, work in progress
1985 XLT 2.8L 4x4 "The Black Pearl" (retired but still around)
1987 XL 2.3L 2wd R.I.P.

clean the MAF.

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(SOLD) 2003 Ranger 4.0L V6 FX4
2001 F150 Supercrew Triton V8 (DD)
2008 Fusion 3.0L SEL V6 (my baby)
1992 Taurus SHO MTX (my toy-almost Supercharged)
2004 Nissan Murano SL AWD (Wife's car)

When you say you changed the idle air control sensor you mean the idle air control valve, it is attached to the TB. a few long shot thoughts. did you pull the neg cable for 20 minutes to let the pcm reboot? super long shot, how is the fuel filter/(should be replaced anyways). air filter?................and i agree with cleaning the maf(only use maf cleaner , do not touch the wire, do the pcm reboot after this)

also i have a cheap Costco code reader $20, when i have an issue like this i check for codes when the truck is acting up. A lot of time the code is pending and then goes away without throwing the cel

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2004 Ext Cab, 4WD, 4.0, Auto, 154k. (4.0 engine is out of a 2009 Ranger w/96k) ( as of 7/1/2017)

2004 Ranger, Ext Cab, 2WD, 3.0, 5 speed , 4WABS, crank windows, no cruise, Edge 116k.(6/5,2014) (SOLD).
1999 Ford Ranger, Reg Cab, 2.5, 5 speed, 2WD, no AC, 150k (SOLD).

i did that but havent cleaned the maf like i said it does it like a cycle, runs good then just drops and runs rough for like 5mins then goes back to running good again..

You did what?

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2004 Ext Cab, 4WD, 4.0, Auto, 154k. (4.0 engine is out of a 2009 Ranger w/96k) ( as of 7/1/2017)

2004 Ranger, Ext Cab, 2WD, 3.0, 5 speed , 4WABS, crank windows, no cruise, Edge 116k.(6/5,2014) (SOLD).
1999 Ford Ranger, Reg Cab, 2.5, 5 speed, 2WD, no AC, 150k (SOLD).

replaced the iat and did a tune up

Try the fuel filter... I had the same problem with mine and replaced the fuel filter and it works perfect! Do it yourself though because ford tried to charge me 300 dollars to get it done.

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2001 Ford Ranger
Edge model
6 Cylinder
3 Liter
Everything stock (as of now)

I guess I will just keep repeating myself and then youdo what you want. I would replacethe Fuel filter. Check the air filter, clean the maf and reboot the pcm. I also would get a codereader and randomly check for pending codes.

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2004 Ext Cab, 4WD, 4.0, Auto, 154k. (4.0 engine is out of a 2009 Ranger w/96k) ( as of 7/1/2017)

2004 Ranger, Ext Cab, 2WD, 3.0, 5 speed , 4WABS, crank windows, no cruise, Edge 116k.(6/5,2014) (SOLD).
1999 Ford Ranger, Reg Cab, 2.5, 5 speed, 2WD, no AC, 150k (SOLD).

i replaced the air filter when i did the tune up and just cleaned the maf the only thing left is the fuel filter but before i do that heres something to think about. When i disconect the front coil pack it runs rough when i disconect the back it just drops idle alittle bit nothing too bad so could it be the back coil pack ? im goin to replace the fuel filter now.

ok just ran the code reader and the only thing i got was p1000 but then i looked it up and it said to disreguard it cuz it was when i ran the code reader with the engine off key on but idk

now what am i stuck with o and i did a fuel pressure test passed with flyin colors

so any ideas on this

also i checked it out im getting 18mpg and thats when im light on the pedal shifting at low rpms but not bogging it and im shutting it off down hills lol long hills any ideas i really need this to be more efficent than it has been. The idle part bothers me but id rather get better mileage.

Seems I am having the same issue. The voltage seems to be low on the indicator and it idles rough from time to time. Dies on idle when first starting up. Once it gets warm it idels without dying, but it will idle rough. 98 2.5 liter