Hello, newb here. My Ranger is giving me some trouble right now. its an 03 Edge with 4.0L manual tranny, heres the problem:

I can start the truck off in first gear, bring it to 2500-3000 RPMs, then I let go of the gas and push the clutch in, at this point one of 2 things happens:

1. After pushing the clutch pedal in, the engine RPMs will stay right where they were when I let off the gas, today I rolled all the way down my street with the clutch pedal pressed in and the engine revving at 3000RPMs all by itself. Once I bring the truck to a stop then the RPMs drop back down to idle. Now I can shift the truck and then use the clutch to force the engine to slow down but it makes the truck lurch quite a bit and I know its bad for the clutch.

2. This is what usually happens, Ill accelerate and then let go of the gas, push the clutch in, and the RPMs will veeeerry slowly start to drop, usually I just have to shift and use the clutch to force the engine to slow down. Also, I get no engine braking, if Im in gear driving and I let go of the gas, sometimes instead of the engine slowing the car down, it will just continue to coast at the speed I had left it at, that part seems dangerous.

Now I had a manual Focus and a Mustang, and in both of those cars, as soon as I would press the clutch pedal in the RPMs dropped very quickly and I had learned them well enough that I would be letting the clutch out just as the engine got to the proper RPMs.

Yesterday I left my truck at the dealer and they replaced the Idle Air Control valve assembly, charged me $300 and it didnt do anything for me except waste $300. I also disconnected the battery for an hour and a half to see if the ECU needed to reset, but that didnt work either. I went back to the dealer today and the service guy said the only other thing he could think of was the MAF sensor has gone bad, I told him I didnt have the money right now to try another thing that "might" work so he told me to keep driving it and see if it throws me a code.

I was thinking I could test the MAF by disconnecting it and trying to drive the truck, without it and see if I still have the problem, but I dont know if thats safe to do or not.I can get a new MAF from Autozone for $140 and install it myself. My bro in law is going to help me check if the accelerator cable is stuck this weekend, but I dont think it is because the truck only does this while it is moving, can rev it fine while standing still.

If anyone knows anything that may be able to help me, it would be greatly appreciated, I'm still a novice when it comes to working on cars, I do my own oil changes, and Ive helped swap exhausts, starters, spark plugs, etc, basic stuff but I no mechanic by any means. Thanks.

Oh yeah I also have a squeak coming from my clutch pedal, and I can hear it from outside the truck well, so now I dont know if its just a linkage that needs grease, or a throwout bearing about to crap out, the truck only has 37,770 miles on it, I bought it in September with 32,400.

 

do you have cruse controll? the clutch pedal has a tsb on it. Technical service buletin. Thee is a replacement part for it and it will take care of it. Does your truck ave ESP on the waranty or not?
The throttle seems to be sticking. For what ever reason. Vac Leak or a sticky spring.

 

I do have cruise control, do you have a link to the tsb? I do have the 114 part ESP on my truck. My bro in law is gonna help me check the throttle on sunday.

I just disconnected the MAF sensor and tried it out and that didnt stop the problem from occuring, so thats not it I guess. Thanks.

 

try cleaning out the IAC valve or replacing it, it did that when mine went out

 

He claims the dealer already replaced it.
Did the dealer service diagnose the IAC valve as the problem?You paid $300 for them to fix it and they didn't.Go back and make them make good on it.

 

The MAF cannot hold the RPM up because all it does is measure the airflow and report it to the PCM. Hanging RPM is caused by more air being allowed to enter the engine. If you have no vacuum leaks, then the airflow into the engine is controlled by the throttle plate and the IAC.

So, assuming that the idle is normal when the truck is stopped, that probably leaves you with an IAC that is open when it shouldn't be.

The IAC can stick mechanically or it can be commanded open. It would seem that you have eliminated a mechanical problem by replacing the IAC.

The IAC can be commanded open when the truck is rolling if the throttle plate hangs open slightly (cable too tight or kinked or out of position) .

It can also be commanded open if the voltage from the Throttle Position Sensor is too high when the throttle is closed against the stop (0.50~1.25v is the acceptable closed-throttle voltage tolerance). Reasons for the voltage being too high could be a bad TPS or a throttle stop screw adjustment that has been tampered with.

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Personally, I'd take it back to the dealer and insist on a refund since they misdiagnosed the problem and it remains uncorrected. If they refuse, most states have a watchdog agency that will investigate repair disputes for free.

 

Yes the dealer said they replaced the IAC valve, When I got it back one of the screws from the plenum cover wasn't in all the way so I could tell they had at least removed that. They said that their diagnostic found no problems, but they suggested that I have them replace the IAC so I told them to go ahead. Im going to go back there after work tomorrow and tell them the things you suggested rwenzing, thanks a lot.

 

Ok am am having a hard time trying to find the throttle body, isn't it supposed to be on the intake near the MAF sensor? Thanks.

 

its on the intake manifold at the end of the Intake hose.. It will have a "TB" extruded on the hose with an arrow. the other side says MAF.

 

The throttle body is under the cover maked "4.0L SOHC". The MAF is at the air filter housing in the DS front corner of the engine bay.

 

OK thanks. IIl check it out later. I thought it was neat the MAF. Thanks for your help guys, Im gonna head back to the dealer after work today.

 

check pcv valve - it won't throw a code.

 

Hey heres an update, I finally got to get the mechanic to ride with me today so I could show him the problem Im having. He noticed it and said its weird, but he said it may be normal operation for the engine to burn off excess fuel so it doesnt go out the tailpipe causing the truck to fail emissions. He said he is going to look into it to try and find if there is a problem. I hope there is because its annoying as hell and I want it to go away.

I also showed him how my clutch pedal squeaks when its operated, said it may b the throwout bearing dying. Good news is he said he thinks my extended warranty may cover the throwout bearing and all service to replace it, if it does, then while they have the whole tranny dropped nyways I will probably pay to have them install a new clutch as well.

As of now Im at work waiting for them to call me and see whats up, fingers crossed.

 

My '06 Ranger had a squeaky clutch pedal. The mech decided it was a binding slave cylinder and replaced. A few weeks later my clutch goes out. They determine that the clutch plates seperated. It was a 2-1/2 week repair because one part of theclutch was on Nationla backorder. Just thought I would give you a heads up and you can have your mech check for any backordered parts before you take it off the road.
No ones can say if the slave messed up the clutch or clutch messed up the slave?

 

Ok just heard back from the dealer, after I rode with them and showed them the problem, they said they cant find any problems, they think its simply the engine burning off unburned fuel in between shifts, so nothing more than can do about it. Im probably going to try and replace the Throttle position sensor on my own though eventually just to see if thats what it is.

They were however able to fix the throwout bearing squeak just by lubing it.

 

Ok my problem is still going on strong, today I disconnected the cruise control, didn't work, then I went and paid $40 for a new throttle position sensor and again, didn't work. Think now Ill turn my attention to the EGR valve/sensor. This sucks.

 

Mine doesn't 'stick' to the rpm once I push the clutch in but it feels like it takes all damn day for the rpm's to go down to match the next gear. Pisses me off, granny shiftin all the time.

 

Heres another update. After replacing the TPS, I decided Id try replacing the PCV valve in case it was leaking or clogged, so I took it out, and yes it was kind of clogged with oil, there was a lot of oil in the tubing coming out of it as well. Put the new PCV in and I still am having the problem. I figured maybe I would try the EGR valve/EGR sensor but apparently my truck doesn't have either.

I went to the dodge dealer today to see what I could do about just getting rid of my truck and getting a wrangler, test drove a clean 05 unlimited with 12k miles for $19,900 and it was really nice, but when I went to talk to thewm about the trade in I told them I was willing to put $5000 down cash if they gave me at least $12k for my truck which I owe $13,500 on. (I figure I can cancel my extd warranty and get $800 or so back and only have to eat about $700.) but when they came to me with a trade in value they only gave me $9500! I just paid like $14,700 7 months ago for it, and that was after I talked them down from $15,500. No way was I going to eat that difference, so I had to leave.

So in short, right now Im left with a truck that I cant get rid of, I cant fix, and the mechanics say they cant find any problems with. My family says its just in my head and I just want a new car so Im making excuses to get rid of it, but I KNOW the engine isnt supposed to keep revving after you let go of the gas, and I KNOW I dont want to take $5000 out of my move out of my parents house savings to pay for a down payment. Not to mention while my truck was getting fixed I drove my buddy's civic with a manual, and it didnt do this, and when I drove that wrangler today, it didnt do it either, neither did my mustang or my focus, so I know Im not crazy.

 

ok first off comparing a civic to a ranger is like saying that a baloon and gravy taste the same. Your truck shouldnt hang up in rpms. Now do a couple checks.
1 check your floor mat Driver side, see if it could be catching on the gas pedal. Its happened to me and some customers {Clutch brake and gas pedals.}.
2 check the throttle cable for kinks.
3 check the pedal for any thing that might be catching on the arm of the pedal.

4 OR your clutch pedal sensor is bad. I have to go with this one. If it doesnt sense the clutch was pressed in the truck will think its still in gear and keep going.

Also Dont replace a part because you think it might be a problem. You might just be waisting money. If you hve to take the vehicle in week after week they will call an engineer in to help fix the problem or also the Lemon law might apply.

 

when it sticks try slapping the throttle quickly to open it up and then let the pedal come up on its own. Kinda like a spring that your trying to shoot. Just let it go and see if the Rpms go below that point after jumping.

 

my truck does this too. but its intermittent and only after startup, most commonly on hot restarts.
i havent done anything about it yet because ive found if i make a COMPLETE stop with the clutch pushed in, the RPMs will fall back to a normal idle, and the issue will not recur during the drive cycle.
seems to me that the PCM is either commanding a slow IAC or an engine with a vac leak to a normal idle once the VSS reads 0mph. im leanin toward a vac. leak, or sticky IAC.

i know you said thats already been checked, but i havent confirmed anything on my truck yet, so i guess im not much help

 

Ah, yet another thread with no deffinitive answers... I guess, I'll go down the list like everyone else and hope for the best, lol!

 

my good friends 3.0 5 spd was doing this last year

we replaced the maf, the sensor that goes in the middle of the intake tube, idr what it was called, and we cleaned the throttle body. that corrected his problem, so maybe it'll work for you

 

I know the year model is way off, but I had an 88 Ranger about 10 years ago that would do something similar to what you are talking about. Check your plugs. 3 out of the 4 had zero gap because they were full of carbon and crap. I gave the truck a full tune up for good measure and everything was gravy after that.

Kris