on my 06 ranger sport is it supposed to be idling around 1.3-1.5k rpm

 

no way thats way too high. i feel mine is high at 1k rpm's but never had issues so i never looked in to it. can anyone add on to this?

 

Mine idles at 750-800. There should be a screw on the throttle that you can adjust.

 

Idle is PCM controlled using the IAC to bypass air around the throttle plate. The stop screw should never be adjusted away from the factory setting. If it is idling too high, check for cable sticking, vacuum leaks, IAC problems. If the truck was purchased used, you could be the victim of a previous attempt at adjustment by the DPO.


1000 RPM is definitely out of spec for a warm engine idle. Typical warm curb idle for most Fords is between 600 and 750.

 

Thanks for clearing it up bob. I didn't even think of there being any vacuum problems.

 

thank you...ill definitely get it checked out! technical stuff like that ill prob leave to the pros at Ford.

 

Mine was doing this and I swapped out the iac and it dropped my rpms to 650ish

 

^^ same here. Swap out the IAC, should only be around 60.00, direct bolt on, no gaskets

 

whats the IAC? newb sorry.

 

Idle Air Control valve = variable air bypass around the throttle butterfly. The IAC duty cycle is adjusted by the Powertrain Control Module to maintain the calibrated idle speed.

 

Sounds like something a prof needs to look at. I know I'm looking at my rpm right now warmed up and it always been at 1000. Always thought it was high but ima get it looked at for sure.

 

i tore apart my engine over the weekend...did a port polish, cleaning, and some painting. i got this gasket kit and i didnt know what one of them was for but i think i just found out. its the IAC. i didnt take all those sensors off the throttle body but if i do and clean the IAC with some cleaner and put the new gasket on, will this help. i mean doesnt look hard to do so i mean even if it MAY help ill do it. but if its gunna cause trouble.

 

That when my problem started. Truck never idled high, except at cold start up. Did some work to it and cleaned the IAC since I had the Upper Intake off. Now I get intermittant periods of high idle when the truck is warm. I won't mess with the IAC until its a consistant everyday problem.

Anyone who has replaced there's have a recomendation on which IAC to use? Junkyard, Any auto store IAC or the Motorcraft one?

 

I just replaced the IAC on my Ranger. It's been having rough running at idle problems for a while now. I'm checking everything, we even did a smoke check for vacuum leaks. Anyway, replacing the IAC seemed to work for about 50 miles then the problem started again. I'm idling at about 1000 RPM and it is higher before it kicks back down. I roll about 35mph if I'm going that speed and it won't slow down.

I'm thinking my problem is the computer. I got this idle issue problem just after I removed the battery cable to clear a code. I can't figure it out. Anyway, I replaced the IAC and it seemed really really good, I thought it was fixed but...nope.

Computer issue (??), but it sure seems like a vacuum problem. Very rough idle clears up "some" when you give it some fuel, One bank of cylinders running on the lean side. It's got a friend who is a mechanic scratching his head.

Cheers,
Gene

 

yea im still working on figuring it out. hoping all the recent work i did on it will have some effect. when i go to pick it up tomoro, ill let you know if its been fixed....make sure your injectors are good. and your getting a good spark. that seems like tis always a good place to check

 

6 brand new injectors, new coil, new plugs, motorcraft wires, new IAC .... I ain't playin !! Timing chainand heads done 10K miles ago. I'm closin in on it fer sur !!

Cheers,
Gene

 

i cleaned my throttle body and that helped a lot it had a lota crap stuck to it it also has better throttle response now

 

yea i got everything cleaned by a machinist. i didnt wana mess with it too much. and yea a IAC and timing chain will be done soon i think haha. need to save a lil first...where did you get your heads?

 

Got the heads from a local shop. I told the owner I wanted hard seats installed in both heads but one of them was bad so I got hard seat on one side now. The first set of heads only lasted 40K miles. Like I said, that is another story. It was my sons truck. The valves were sunk into the heads at least 1/4". All of them in that short a time. It wasn't my truck at the time.

Good Luck,
Gene

 

Computer problem sounds good. I doubt I have a vacuum leak, as it is such an incosistent problem It idles hight sometimes and others it don't. When its not idling high normal idle is about 1,000 to 900 now. It should be 600 and then 700 with AC on. After a good long 20+ mile drive it will idle at 700. I know Ford had a TSB on replacing IAC valves on these. I haven't read it in so long I don't remember what it said.

I guess this has been a known issue for a long time. Ford was getting a huge amount of IAC sent back for warranty repairs, and they all were testing good, so they issued a TSB to check out a few things before replacing the IAC. If someone can find it please post.

 

Yea ill have to check those two things out...i got my truck back today seems to idle at 900 and 1000 like you were saying. i been thru too much with this truck. ill prob just leave it alone.

yea i had 6 cracked seats. was gunna cost me 600 bucks for a valve job. i ended up buying reman heads. everything is working nice and smooth.

 

I bought a multi meter, borrowed some wire piercing leads from a friend and I 'm gonna pull the throttle body. First, I'm gonna replace the plug wires. I jsut bought a new set from NAPA, the premium ones.. I'm gonna check andc clean the MAF and other stuff, change the oil etc... I'll be playing the rest of the day for sure.

Touchdowns everyone !! LOL
Gene

 

Now ya see...this is why some people curse. New wires (the old ones were only 10K miles old), pulled MAF and cleaned, pulled the Throttle body and cleaned it up real good. put it all back together and am now preparing to do other checks. The truck laughs at all this and does exactly what it did before.

I disconnected the IAC (the new one I just put on) while the truck was running...no change..it still took a minute to idle down on 1000RPM. It seems so much like a vacuum leak but we did a smoke test and didn't find anything a few weeks ago, removed the plenum twice and checked for leaks. Rough idle as usual. As soon and the throttle is cracked open the smallest amount, the idle jumps and stays there.

The Long term trim (??) on the drivers side of the truck is -14 while the other side is 2. This is consistent every time I check it. Danny says it's leaning out for some reason. O2 sensors are working. I was thinking about swapping them.

We swapped the injectors a while back so and they are all new so...

I'm still thinking vacuum leak as I hear a squeek sound but that could be the mounts moving around.

Hmmmmm.... (difficult to rule out the computer)

And how was your day? LOL

Gene

 

humm thats a clue that the trucks idle doesnt idle down after your unplug the bypass valve(IAC). when i disconnect mine, it idles down, telling me that the computer is telling the valve to stay a little open and keep the idle higher. if it doesnt change, the IAC might not be working. not sure.
and yea when i tap the throttle a lil it jumps up and takes a moment to come back down and sometimes it takes longer for it to return to 1000. sounds like our problem is similar.
not sure what else can cause it to want to idle so high up.

hows your coolant and temperatures?

and my day has been boring, im up in CT so were awaiting this hurricane to come thru.

 

Coolant temp is fine, my IAC is brand new, the computer is definitely telling it what to do. Now that I've replaced the plug wires I doubt I'll get another misfire on number 5. We'll see. My friend checked the injector pulse and it was good.

Somebody said they plugged the hole in the throttle body butterfly. I tried that and the idle came down with the IAC disconnected. I think it ran smoother but all that would prove is that it is getting too much air, it doesn't necessarily mean the throttle body is the problem but....I'd like to swap one out to see.

The more I check the more I believe the computer needs to be reflashed. None of the idle problems existed till I disconnected the battery for 20 minutes. I can't imagine a smoke check not revealing a vacuum leak but I wasn't there. I've been over every inch of the engine 20 times...I can't find anything loose or leaking.

I wonder if I can manually check the timing....with a light.

<he ponders> LOL

Till tomorrow...after lunch. Then....it's on again.

Take Care,
Gene

PS Hope you guys have minimal issues with the hurricane. We were in the eye of Katrina.