Intermitant problem

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Oct 22, 2001 | 08:56 PM

wbtguy

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Intermitant problem

Hey, maybe someone out there can help. I have an '84 F-150, 4x4, strait 6 300. Often my truck will idle really high, its really annoying, and sometimes it wont. I recently replaced the EGR line from the manifold to the carb because it was rusted out, and now it runs alot better that the chokes opening.... this was about two days ago, and today it started to idle high again once it got warmed up. Any ideas, sugestions, anything would be appreciated.
Eric

Oct 23, 2001 | 01:42 AM

Fordtruxrok

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Intermitant problem

Check to see if the fast idle cam is turning, it may not be coming off fast idle.

John

Oct 23, 2001 | 08:17 PM

wbtguy

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Intermitant problem

I have no idea what that is..... But tongiht, it started doing it again, so i poped the hood while it was running high, the throttle plate (or whatever the metal bracket the throtle cable attaches too) rests on a little metal cylinder coming from what looks like an electrical selonoid or something, well, while it was running really high, that cylinder coming from the selonoid thing was sticking out about 1/2 inch farther than normal, so, the throttle resting on that was forced to stay open....now...what do I do about it?

Eric

Oct 24, 2001 | 01:08 AM

Franklin2

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From: Virginia

Intermitant problem

Your truck has a computer doesn't it? I just looked in my book and it says that this thing is supposed to reduce emmisions by holding the throttle open a little while decelerating. It has some sort of electronic box/and or computer plus some vacuum line stuff. If I am describing what you have, I hate to say it, but I would disconnect it. The only one of these things I have seen that have a useful function, is to raise the idle when you turn the air conditioner on.

Oct 24, 2001 | 07:35 AM

quads

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From: conneaut usa

Intermitant problem

If my memory serves me correct that is what they call theb ISC motor stands for idle speed control motor it electronically moves the plunger out to hold the throtle open if thats bad that could casue it or it could be the tps sensor thats where that gets its signal from first of all run a code test and see what it tells you the best way to start
Godbless

Marc Conley
Morganton Nc
82 F-100
W/302

Oct 24, 2001 | 07:44 PM

wbtguy

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Intermitant problem

Hey, thanks guys.
Quads seems to be describing it almost perfect, it doesnt have any vacume lines or anyhting to it at all, just four wires coming out the back into a harness. Today, it was idleing really low... I'd have to give it gas to keep it alive, poped the hood and the plunger wasnt even touching the throttle, so that probably is whats wrong. What is a code test though?
Thanks for all the help, I really appreciate it.
Eric

Oct 24, 2001 | 08:48 PM

Mil1ion

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Intermitant problem

https://www.ford-trucks.com/dcforum/User_files/mil1ion/3bd76f762ccb3a08.gif
https://www.ford-trucks.com/dcforum/User_files/mil1ion/3bd76f612c3c26f5.gif
You can purchase a code reader for code retrieval (Code Test)
from pratically any auto parts place.
Equus makes two or three different ones for Ford Vehicles and they are resonably priced.
To me it's a must for a do-it-yourselfer.

Dennis

78 F-150 429CJ 465,000 KM.(Original Owner)
68 Mustang 289 Sunlit Gold 80,000 Miles(second Owner)
64 1/2,260 Pre-World's Fair Mustang #8092
64 Fairlane 500 S/C,waiting for a 390 4-Spd

If The Girls Don't Find You Handsome,
They Should At Least Find You Handy!