Hey y'all, I'm having a problem with my 2000 2wd 2.5L Ranger stalling after disengaging the clutch while cruising to my first stop after a cold start-up (been happening for at least 6 months). If I let the truck warm up in the driveway for 5 minutes or so before I start driving, I don't have this issue. Additionally, if I throw the truck back in gear after stalling while still cruising, truck starts right back up again. If I come to a stop after stalling, truck has a tough time starting back up and usually needs to be cranked a few times before staring up with a very rough idle. A couple other issues to mention that could coincide are general decrease of power/acceleration than in the past, a pesky P302 code (cylinder 2 misfire) that has been around for almost two years and sometimes hard to move shifter into gears or out of first at a stop (clutch pedal depressed all the way but still creeping forward).

Work that has already been done that may relate to issue(s):
- TPS and fuel pressure tests passed (1 week ago)
- Ignition coils replaced (1.5 months ago)
- Shop tested for vacuum leaks, none (2 months ago)
- Fuel pump, filter replacement, ECM and Fuel pump relays replaced (2 months ago)
- O2 sensors replaced (8 months ago)
- PCV valve, IAC valve and 2nd cylinder fuel injector replaced (14 months ago)
- Clutch, pressure plate, master & slave cylinders, throwout & pilot bearings and tans fluid replaced (20 months ago)
- Spark plugs, ignition wires and thermostat replaced (2 years ago)

Ideas I have for what could be wrong:
- IAC valve (dirty?)
- Crankshaft or Camshaft position sensor (don't know how these would perform differently at cold start-up)
- MAP, IAT, ECT, EGR (haven't read much on these)
- VSS (don't know how this would perform differently at cold start-up and unclear where or how many there are on my truck, sources have varying information on location and how many and some say it's same as ABS WSS for my model)

If anyone has experience with this issue and or opinions, I'm all ears!!

Welcome to the forum

Does engine idle high, 1,100+ RPM on cold start, it should, that means IAC Valve and ECT sensor is working
Idle should drop down on its own over the nest 5 minutes and settle in at about 750 on a 4cyl manual trans, maybe 800
4cyl engines vibrate too much under 700 because of 180deg firing

First lets see if you have an Anti-diesel adjustment screw
Look on the throttle linkage for a "stop" screw, "looks like" an idle screw
Ford was starting to eliminate those in the late 1990's but the 2.5l engine was a hold over so may have it
If you see it then adjust it to eliminate the stalling, doesn't fix the issue just prevents the stalling
Warm up engine fully
Unplug the 2 wire connector on IAC valve, valve will close, idle should drop
If engine stalls turn the anti-diesel screw 1 turn clockwise(tighter)
Restart and see what idle is at now, should stay running now
You want idle to be 600rpm with IAC Valve unplugged
Plug back in IAC Valve and idle should go up to warm engine target idle
Unplug it again and idle should drop but engine should not stall
This screw also changes the TPS minimum voltage, which should be under 1volt with throttle closed, so don't screw it in too far, you just want engine to barely be running, its NOT an idle screw, IAC Valve needs to set the minimum idle based on engine temp(ECT sensor)

Yes, could be dirty IAC Valve but usually idle stays higher not lower

IAC Valve is a 12volt solenoid, the computer controls its voltage via the Ground side, its a very accurate way to control air flow into the engine, +/- 4rpm is spec
The computer "learn" the voltage it needs to set the IAC solenoid at for say 1,000rpm, 900rpm, 800rpm or 754rpm, lol
And its constantly updating the voltage used
When you take your foot off the gas pedal the computer sees that via the TPS, under 1volt, and it sets IAC valve voltage for idle, something is wrong if your engine is stalling

You can only use Motorcraft or Hitachi brand IAC Valves, as these are true solenoids, other brands are step motor/solenoids so "work" but will act up


You have air in the hydraulic clutch system, needs to be bled, common issue on Rangers
Clutch is not disengaging fully , when you are stopped is when you notice it the most

Here is a link for the Hitachi IAC valve for the 2000 2.5L Ranger just in case you need to get one.

I just installed one on my Ranger yesterday.
Just be aware that it took me 16 days to get the part. So if you need to order one don't take yours off until the new valve is delivered.
I was having the same problem with stalling and extremely rough idle(under 700rpm) if I didn't let the vehicle warm up completely.
I tested my original Motorcraft IAC by disconnecting it with the engine warmed up and running and there was no change in idle.( Following Ron's advice). After tapping on the IAC the idle did drop a little when disconnecting the valve but the stalling problem remained.
That's why I ordered the new Hitachi IAC valve. I haven't had a chance to drive it yet since installing the Hitachi unit so I can't say if the issues are history or not.

Thanks for sharing all this information RonD! I do not have a tachometer so it's hard for me to tell what the rpms are at any given time. By listening I can tell the engine does idle high on cold startup and slowly drops over the next several minutes.

I adjusted the "stop" screw on the throttle linkage so the voltage to the TPS sensor reads 0.98 (previously at 0.94), The truck still stalls after unplugging the IAC, but is definitely a little bit happier driving from a cold start up without waiting for the engine to warm up. Truck has still stalled while driving, though not as often as I would expect. Should I potentially tighten the "stop" screw further and go over 1 volt on the TPS? I'd like to also note that WOT only registers 4.44 volts at the TPS. Should this be a cause for concern? I was reading another thread that you commented on stating that WOT should be 4.5+.

Another detail I haven't been considering as much that may help diagnose the issue is the fact that when I do stall while driving, the engine has a tough time starting back up again. I almost always need to hold the key to crankover for 5-10 seconds until the engine fires up. Any rationale behind this?

I replaced the IAC valve about 14 months ago, I bought a cheap Walker replacement off rock-auto. Perhaps the fact that I'm using a step motor/solenoid is contributing to the issue I'm having.

Air in the clutch hydraulic system is what I've been suspecting as well. I've tried bleeding to no avail. Based on my research and the angle of the clutch pedal rod, it seems as though I may have to take the whole master cylinder system out, bleed it upright and reinstall.

EdK, Have you driven the truck since installing the hitachi IAC and has it remedied your issues?

Cycle the key on and off 3 times after the next Stall and see if that helps it restart faster

Test voltage at the battery after engine is warmed up and idling, no lower than 13.5 volts is expected
Don't restart the engine, test it after you get home, or after its been idling 5 to 8 minutes, leave engine running and open the hood to test it

The 4.44v should be fine

Yes, I have driven it since installing the new Hitachi. The truck does warm up better and no longer stalls and tries to rip out the motor mounts if I drive it before it fully warms up. So that problem has been fixed.
However, I've been noticing that when I try to raise the rpms to let it warm up the engine rpm drops down to idle even though I didn't let off the pedal at all. This only happens right after I start it, then after a bit but before the engine warms up I can hold it at a fast idle.
My Ranger doesn't have a tach either so I can't post any specific rpms unless I hook up my Blue Driver scan tool.
Between gears with the clutch in it also tends to rev a bit high, but without a tach I can't say if it's within the normal range or not.
I think it's possible the situation with the rpms dropping on their own and the high revs when I shift might be the computer relearning with the new IAC hooked up. The check engine light hasn't come on and there are still no codes.
I have to wonder what Ford was thinking when they decided to equip all automatics with a tach but not the manual trans vehicles, but I digress.
As far as your truck is concerned- As RonD has pointed out the only IAC units that will work properly are either Motorcraft with the right part number, or a Hitachi with the right part number.
So maybe that is what is causing your issues.
I had initially bought a Dorman IAC from Autozone but luckily I read Ron's post before I installed it so I returned it and ordered the Hitachi. I'm sure that saved me some headaches so thanks again Ron.

Regarding clutch bleeding:
Here are a couple videos I have found while searching so I can do my own clutch at some point.

This video is Part 1 of 2, showing how to bench bleed(or burp) the entire system.

This is Part 2 showing the on vehicle procedure.

There are other videos available but these two are Ford Ranger/Mazda B Series specific.
Note: Due to the angle of the master cylinder in the vehicle it is better to remove the whole system and bench bleed it to get the air out of the top of the M/C.
Prior to removing the system you should check the Slave Cylinder first by removing the rubber inspection cover on the side of the transmission. If you see fluid all over, you probably need a new slave cylinder. You have to remove the transmission to remove the slave cylinder.
So to recap:
8 hard to reach spark plugs in a 4 cylinder.
Slave cylinder buried inside the tranny rather than on the outside like a normal car or pickup.
PCV valve buried in the block rather than in the valve cover.
Master Cylinder mounted at an angle that insists on trapped air in the system.
Tachs in automatics but not manual vehicles.
There must have been some very angry, hateful people designing this engine. Actually I'm pretty sure it was designed to force people to crawl to dealers to have even simple work done and pay out the 4th point of contact for the privilege. But I could be wrong.
Anyway, I hope you get your Ranger running like it should. With all the head scratch inducing design flaws and weirdness going on, they're not bad little trucks.
I'm just getting started on mine and it's been a learning curve to say the least.

You can bleed the air out of the system while the master and slave are "in the truck" you just need to remove the master and turn it upside down

I'm also not following the "no tach in a manual" statement. Mine has a tach, almost all the manual rangers I've seen have a tach. Odd that yours does not have one.

If you check HERE I outlined the steps I take when I bleed my system. I do not have the "luxury" of Ford's quick disconnect system, so it all gets bled in the truck, at once.

So you think I'm making it up? Okay, so yours has a tach. Most I've seen do not.
I'm not here to argue.

So you think I'm making it up? Okay, so yours has a tach. Most I've seen do not.
There are a lot of videos and forum posts of people with manual transmissions looking to swap their instrument cluster for one with a tach. Most of the clusters that have a tach come from automatics.
Believe what you want, I'm not here to argue.
As far as bleeding the clutch system in the truck, I'm simply posting what the majority are saying to do.
If turning the Master Cylinder upside down works, then great. I haven't tried either method yet.

Sorry about the double post, I tried to edit the first one.

Double post is fine, it happens.

I also am not here to argue, LOL. Just strange that I've seen most all of them witha tachometer, and you have seen them without.
Just an interesting difference in experience, is all.

With bleeding comes disconnecting the master from the slave. In doing that you compromise the quick disconnect. Which is exactly what happened to me. While driving.
Replaced the master line 2x since they continued to pop out of the slave, and had enough of it.
Replaced it with a single -3 line from the master to the slave, and haven't suffered the issue since.

The Q/D is convenient, but should honestly be made differently. The earlier models had a Q/D similar to a sharkbite, the 99+ have this weird c-clip type design that honestly sucks. The master side of the Q/D (male) was the part that failed on me, but an aluminum fitting being held in place by spring steel is going to shear off in time, no matter the brand.

I think I am going to bleed my clutch again, Just had a clutch job done and I think that I can do a better job bleeding it than they did. I do not know how to bleed it in the truck "just turn it upside down. I have taken it out the floor board and bled the clutch on with it still connected to the slave before if that is what he means. Its a shame that it is so hard to bleed.

Thanks


BOB

I did a bit more digging and see that TurismoLover left a link describing the procedure.


Thank you,

BOB

Its been a while but I'm still having issues with stalling after cold start. I've since replaced the IAC with a Hitachi brand one and replaced the camshaft position sensor with no luck. My next thing to try is replacing the crankshaft position sensor. However, my haynes manual doesn't seem to describe the 2.5l 5 speed manual CPK setup accurately, it refers to a two bolt sensor when I only have a single bolt sensor and I can't find any videos with my engine in it.

Big question: can I replace the sensor without removing the crankshaft harmonic balancer and realigning teeth and making timing adjustments etc

There seems to be enough room for me to do that.

I now have the complete Ford official shop repair manual set for the 2000 Rangers.
Let me take some pics of the Crank Position Sensor removal/ installation and I'll post them here sometime tomorrow or Sunday..
Regarding the IAC valve- I ended up putting my old Motorcraft IAC back on since I had high revs between gears and with the clutch in at stop signs etc, ever since I installed the Hitachi unit the year before.
I had already cleaned my Motorcraft IAC before installing the Hitachi and kept it in the Hitachi box so it was ready for reinstallation.
I've been looking for a Motorcraft IAC for awhile now. I had a part number from the local Dealer but I can't find it anywhere. You might want to try your local Ford Dealer and see if they can give you the right part number for your truck. You'll probably only find the part on eBay or similar, unfortunately.