Engine Problem: Low Idle/ Stall

[BootyDo]

Hello,

I have a '99 Explorer that's just short of 100k and am starting to run into something. Specifically, the engine idles low and even stalls at times if I do certain things.

I'm not too sure how long ago, (probably since I got it 1 1/2 years ago), the engine idled rough. I've since had all the spark plugs and spark plug wires changed. When I thought things were getting worse, (it idles at 500), I bought a whole new Idle Air Control Valve. Nothing. I then picked up some of that Mass Air Flow cleaner and sprayed the heck out of it. After it reprogrammed, it idled around 900. But once it really got warmed up, it was back to the 500 rough idle.

Right now, if I tap the gas and immediately tap the brake, it'll stall. And when it's just moving on a drift, (like parking), it really sputters.

Should I just manually adjust my idle and, if so, where is that?

Thanks!

 

[Togman]

I did that on a 99 I use to have, but not too sure how safe it was as it idled high when cold, then it dropped back to where it needed to be and I got use to it. I think it was near the Throttle Sensor, it was a bolt with paint on the threads.

 

[BootyDo]

Thanks for the reply! One question: When you did that, aside from the unusually high idle in the cold, was there any other adverse effects?

Thanks!

 

[Hoppy]

I just had this issue on my 00 ex.

I cleaned the throttle body, it was so badly carboned up that when it closed the valve would basically seal itself shut. The air bleed hole in the throttle plate was blocked shut as well.

After cleaning it (by taking it off of the intake) it has started much much better, it actually has a fast idle again, does not stall any more and has a very nice smooth idle again, not shaking the truck like it used to.

Another thing that could be your problem is a dirty MAF sensor, IAC valve, which you said you cleaned, or an ECT sensor.

 

[Togman]

Yea, good idea, clean the Throttle body. I think I went too high & had to play with it to get it right, but for some reason it was the only thing I could do to get the throttle back. NOt something I would reccomend everyday cause if it was meant to be, ford would tel you how to do it.

 

[BootyDo]

Thanks for the replies all! I really hate to sound so pathetic, but is there a how-to on cleaning the throttle body? I think when I removed the IAC valve, it was exposed.

Would Seafoam be a good alternative?

 

[DieselDean89]

hey man, dont feel bad, im in college right now to become an auto/diesel mechanic and i cant even fix my X! i have a '99 XLT 4.0L SOHC with a rough idle too, not so much the stalling (its happened but not frequently), also my engine is running lean, so i figured too much air means not enough fuel right? so i tried seafoam in my gas tank. didn't do a thing. so like the other guys said, probobly just a bad ECT (Engine Coolant Temperature) sensor, or contaminated MAF. but yeah save yourself $9 and dont get the seafoam

 

[bozo4ford]

Idle Air control Valve - '86 Ranger 2.3L gas EFI

Did you ever find out about your problem? Was it indeed the IACV valve?

I'm having similar problems and I posted in today's 2-15-2010 FORD RANGERS>

"1986 Ranger 2.3 gas-putting & stalling after replacing spark plugs, etc. " Mine Idles for 35 seconds then stalls out.

Any pictures of where it is and what it looks like?

 

[kanaka913]

Heyy guyz ...all good information. I'm glad I joined up. I've go a 02 Exp Limited V8. I have the same idle problem as described above and after changing plugs (104k miles) and checking every hose, etc I considered putting the idle up. Will deff try the cleaning of the throttle body and see if that helps. Question regarding the ECT, would you get an engine check light? If not then how would you know it was defective? thanx

 

[Cardfan99]

Just cleaned my throttle body and did the battery/light switch. It worked but my truck just experienced this at 253,500 miles. Thanks!

 

[Blue Oval Charlie]

Just cleaned my throttle body and did the battery/light switch. It worked but my truck just experienced this at 253,500 miles. Thanks!

Read this thread because I used to have this problem.
Cleaned the Throttle body and MAF, replaced IACV (which was actually bad) and smoke tested for vacuum leaks. Throttle body clean worked for a while.
Did a free VIN search, read list of recalls FORD recalled the throttle body due to a defect that caused the plate to stick.

 

[koda2000]

500 RPM idle is too low for a 5.0L V8. It should be around 650 RPM. Three things you can do...

1. Clean your throttle body.

2. Adjust your IAC valve (some have Allen screw for this purpose). Turning the screw one way will raise your RPM. Turning it the other way will lower your you idle RPM.

3. Adjust your throttle plate stop screw to open your throttle plate slightly to raise your idle to around 650 RPM