embarrassing novice question

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Jun 6, 2002 | 06:35 PM

oldblue18

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From: Georgia

embarrassing novice question

My f-150 has a bad habit of the throttle sticking. It is quite annoying because if I am driving down the road at 3000 rpm and depress the clutch to shift the RPMs do not decrease until I let the clutch out again. It's the same story at a red light. The engine will remain at what ever RPM I was driving at until I let the clutch out again. It is not only annoying to me that I have to slip the clutch everytime I shift or stop, but I have 12" glasspacks on true dual 2" pipes and some of the cops around here might think I'm trying to show off in front of them.

I've tried PB Blastering the ends of the throttle cable(at the pedal and at the throttle body) but how do I oil/lubricate the rest of the cable? Also it did a funny thing earlier this week, I was letting it idle in a parking lot while waiting for class to start and all of the sudden the engine revs up to 3000 RPM--all by itself--my right foot was on the brake and the left was against the door, the tranny was in neutral.

So what else can I do besides lubricating the throttle cable? Any ideas on what else I can do?

Thanks y'all!

Jon
1989 F-150 XL- 4x4, 302, M50D
1995 Bronco Eddie Bauer- 351W, E40D
Finally got around to creating a gallery...check it out

Jun 6, 2002 | 08:08 PM

topo4u2

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embarrassing novice question

Hi Jon,

That truck sounds like it has its own idle. Well, let's see now. You can test the throttle cable by disconnecting it from the intake and testing it without the throttle plate connected. At the same time with the cable off you can check your throttle plate for sticking. If that idle is going up in its own you may have a sensor at fault so see if any lights go on at the dash especially the "orange" check engine light. Let me know what you find.

Jun 7, 2002 | 09:09 PM

BroncoScott

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From: Florida East Coast

embarrassing novice question

If the truck has a wandering idle and the cable is fine, you need to clean the idle air control valve (IACV). Got a Haynes or Chiltons manual for the truck? If not get one. You will need to take the IACV off and carefully clean it. They get sticky from carbon or if you have oil blowby the can get a little sludgey in there.

Jun 7, 2002 | 09:47 PM

oldblue18

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From: Georgia

embarrassing novice question

Thanks Scott and Mike, I'll try those first thing after the weekend monsoons pass

Don't you know as soon as you want to go out and work on your truck it pours down rain--this is the first rain we've had in south GA in 2 months!!!

I have both chiltons and haynes and I'll try the IACV trick if it isn't the throttle cable...

Now that I have thought about it, it did give the code for a TPS fault a couple of times but it ran fine so I ignored it...but that was last fall... about 6 months before these symptoms showed up...Oh well...

Thanks again

Jon
1989 F-150 XL- 4x4, 302, M50D
1995 Bronco Eddie Bauer- 351W, E40D
Finally got around to creating a gallery...check it out

Jun 8, 2002 | 12:50 AM

gamehunter

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Joined: May 2001

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From: Coon Rapids, MN

embarrassing novice question

That is probably your best be to check the IAC. If that for some reason doens't work or only works for a while, check your vaccum hoses for leaks by spraying carb cleaner on them and listening for the engine to rev. I think I might have a small leak somewere but right now I have other things to worry about.

Jun 8, 2002 | 10:31 AM

MR GOODWRENCH

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embarrassing novice question

Jun 8, 2002 | 03:04 PM

oldblue18

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From: Georgia

embarrassing novice question

I checked the IACV this afternoon and it was already loose--so I removed it, cleaned it out and replaced the o-ring. It idles better now and doesn't rev-up by itself any more.

Thanks again y'all!

Jon
1989 F-150 XL- 4x4, 302, M50D
1995 Bronco Eddie Bauer- 351W, E40D
Finally got around to creating a gallery...check it out