Hi guys. I know I don't post on here much at all, but I could use some advice on my 88 F-150 throttle cables. My 5.0 has been suffering an erratic idle since I've owned it, and now when I exit the free way, or end any 55+ driving area, when I come to an intersection, it wants to idle down to 500 or so, lose oil pressure and die.
It isn't low on oil, and only does this when on the exit ramp, or similar. Both of the cables at the throttle body are broke, the one with the plastic inner sleeve, and the one that has the plastic tab, that fits into the bracket. One is the throttle, the other for the cruise.

Is there an inexpensive fix for this? Or do I have to suffer with it? Where can I buy new throttle/cruise cables?

 

You need to clean the idle air controller. There are instructions for this in both the late 80s forum and the 302/5.0 forum.

 

OK, I'll look them up. But the cables them selves are not part of the problem?

 

If the cables were the problem, you'd have a high idle condition.

 

I went ahead and bought a new IAC. As soon as it stops raining, I'll try and swap it out. I'll keep the old one, clean it up for a spare, just in case....

 

Well, I replaced the stupid IAC. Piece of cake, two bolts, ten minutes.

Now, the truck doesn't idle for crap. Let me rephrase that, it idles high, and acts like the clutch position sensor is out of whack. Like if you are trying to merge onto the highway, give it gas, step on the clutch, remove foot from gas pedal, the thing will rev itself to like 3K rpm's.

High idle in all conditions.

Is there a common check list or diagnostic posted some where for this?
And, since the truck is an 88, it is an OBD I, right? Where is the diagnostic port located?

 

The late 80s forum and the 302 forum can both give you the proper information. Usually cleaning the IAC helps, that's why I recommended it, but go to one of those forums for more info.
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