Hi all! I have a 1995 ford ranger v6 4.0 and for this week Ive been having a problem, stalling... It only happens when I do quick "stop and go" driving. Even sometimes at stop lights it wants to stall, the only way to keep it going is to keep my foot on the gas. Now for a while when its cold or my truck has been sitting for a day or two the truck doesnt start on the first click. Ive had the fuel pressure checked, changed fuel pump, and starter.
I have no check engine light on at the moment. Tomorrow Im gonna check with my scan tool just to make sure. But do you guys think it could be fuel pressure regulaor, idle air control actuator, egr valve? Whats your thoughts about how I should go along doing this?
Thanks and happy new year!

 

If it has an auto tranny, try quickly shifting to "N" when coming to a stop & it begins to act out & tell us if that stops the stall.

Did you resolve your evap system troubles, like replace the loose dry rotted vapor recovery charcoal canister line & change out the loose fitting over size replacement AutoZone sold you??? You never closed out this thread.

Did you get the fuel pressure check done & inspect the fuel rail pressure regulator vacuum line to see if its wet with fuel inside??? You never closed out this thread either & these things can mess with idle speed, so the forum needs feedback on your open threads that have to do with idle woes.

The IAC = Idle Air Control is responsible for maintaining proper under load engine idle speed, so I agree it probably belongs on your suspect list.
So to test it, if when at idle it acts out when we turn on the A/C & the compressor adds engine load, or we turn the steering wheel & the P/S pump adds engine load, or it stalls when the auto tranny is put into gear, or it stalls when coming to a stop with the auto tranny in gear, or if when at warm idle, the idle speed or quality Doesn't change when the IAC electrical connector is Disconnected, suspect problems with the IAC.

If it doesn't stall when the auto tranny is quickly shifted to "N" when coming to a stop, suspect the auto tranny torque converter isn't unlocking.

If you come to suspect the IAC, you might try removing & cleaning it with its electrical connector end elevated, so solvents & crud don't run into that end & dissolve the solenoid windings wire insulation, or muck up the mechanicals & cause mischief.
If you'll use a plastic & electrical safe spray cleaner like MAF sensor spray, you'll likely have less chance of causing other problems.

Cleaning the IAC may not last, it didn't for me on my 99 Ranger & is probably why Ford suggests replacement when they act out, but cleaning mine was a good trouble shooting step for me. Motorcraft, or BWD are recommended replacements if it comes to that.

Good idea to scan for trouble codes, so post All code Number clues found, as they can help focus a trouble shoot.
A bunch of thoughts for consideration, let us know how it goes.

 

Hi, yeah I havent fixed that hose, the only reason why I havent is that the code that I was getting for that problem hasnt came up again. Do you think that could still be causing the problem? The zip ties I put on the hoses are pretty tight.

I checked with the scanner, no codes stored. I wish there was then I could find the problem!

Now I havent put it in neutral (I just saw your reply) (I took a look at the truck this morning) Now in park, it still stalled. Reved up and down quicky and a slight howl happened and the engine slowly died. Starts back up after that and the rpms go really high up. then go back down to around 1000RPMS. I also forgot to mention my idle is usually like 600RPMs most of the time I stop (after ive been driving for a while)

Tomorrow ill try to troubleshoot this more

 

Oyeah, I did get the fuel pressure checked and everything was fine.

 

OK, good feed back on getting the fuel pressure tested & it being ok. Post the fuel pressure numbers you got & if you also tested for volume delivery over time = 1/2pt/15 seconds typ & how long it'll hold fuel pressure. Also scanning for & not finding any stored trouble codes. Be mindful that a acting out IAC might not set a trouble code!!!!
Next time it acts out & try's to stall when coming to a stop, quickly shift into "N" before the stall & see if that stops the stall. If it does, suspect the torque converter isn't unlocking.
Try the other above suggested idle speed load tests & let us know how it goes, in case you have more than one problem.
I don't know what to suggest about the vapor recovery hose, as we can't determine how much "oversized"/loose fitting the AutoZone hose was, nor how to calibrate "pretty tight" on the zip ties???? Its your call on that one, but yes if the hose or connection is leaking vacuum it could cause idle woes. Keep us posted on your idle speed & shifting to "N" when coming to a stop tests.

 

Thanks for getting back so quickly, Ill take another look at the hose, might as well get the right side hose anyways. But yeah Ill check if going into netural will stop the stall or not. Also ill fool around with the IAC, read a few different things I can do to test it. #1 I can unplug the IAC and restart the truck and see if the idle rpms have changed or stayed the same. Now I got this from a book repair guide, now dumb question but should I just disconnect the wires or should I take off the valve?
#2 Checking the resistance of the IAC to see if its "right".
Ill let you know what I find.

 

The surest way to check the IAC is as I outlined above, by disconnecting its electrical connector at warm idle, rpm should drop, the engine may run rough or stall, if its working. If nothing happens, the IAC isn't working.

 

OK! So I checked the IAC by unplugging it, the second I unplugged it the trucks idle went down (didnt turn off).
I also checked the hose that I replaced and I can bet dollars to donuts its not that.
I tried to stall the truck but it was too stubborn today, it almost but never did (I also tried putting it in N and the rpms went up). Still iding around 600 rpms in drive after those hard/quick stops.

Also side note since my first post since the stalling was getting worse, the heat isnt working in the truck. I tried it on every setting and it only blows cool air. I checked the coolant hoses that go to the heater core and they are both warm to the touch. And there is coolant in the resevor. Havent checked the radiator. Also unplugged the vaccum that connects to the heater control valve to see if that would do anything and still no warm air. Also I noticed my engine temp went from between cold and hot to right above the cold side (minimum operating temp).

 

Ok, good feedback on the IAC unplug test, sounds like its working, as the rpm dropped, as it should. It's supposed to drop to "curb idle", in preparation for engine shut down, as when happens when we power the engine down by turning the ignition key off, so we don't have run on/dieseling, upon shut down. Its not unusual for the curb idle rpm to drop to 500-550 rpm, so as previously mentioned it'll likely run rough, or maybe stall on the IAC disconnect test, but its supposed to do this & indicates the IAC is working.

On the engine coolant temp condition, it sounds like the engine thermostat is sticking open, maybe time to replace that puppy with a like one with the air bypass valve, so the system can easily burp/bypass air back to the top of the radiator upon coolant system refill.

Be prepared to quickly shift to "N" if it tries to stall on a quick stop, as that can tattle on the torque converter not unlocking.

Sounds like you had/have several ongoing problems that may have/are playing into the stall problem, so next get the engine coolant temp problem put right & continue to monitor the quick stop stall to see if it returns & let us know how it goes.

 

Ok well ill order the thermostat, should get it by Wednesday.

 

Pawpaw, is it the brake light switch that disengages the converter? Maybe a quick brake light check would eliminate the switch.Or is there a separate one for the converter...I don't know a simple check for this.

Sure seems to be an idle issue.

 

Yeah, last time I checked they were working, Ill take another look tomorrow morning though.

 

OK sorry for the long wait, I changed the thermostat and the coolant myself. That did fix my temp gauge problem. The no heat I was getting I had to bring down to the shop, it was the motor that moves the flap from warm to cold arm. Will my truck was at the shop I did mention that I was having a idle problem. I had him check the computer to see if there were codes and there was nothing *I already knew this because I also checked before hand.
Now Im starting to think its a fuel pressure regulator? My truck has a hard time starting up in the mornings (cold mornings) and it usually works fine when I turn the power on the car on for a few seconds, off again, then try to start and it starts right up. I still think its SOMETHING to do with the fuel pressure. I had the fuel pump changed/fuel filter last year.
Thanks

 

if you've come to suspect a fuel pressure problem, have you performed a KOEO fuel pressure test in the morning before cranking the engine for a start??? Have you performed a volume delivery over time test & a pressure leak down test????

 

No I havent personally. My mechanic has and he has checked and the pressure is normal. Although I find it hard to believe.