Accelerator cable causing engine shutoff in Neutral?

[DracoSedentis]

Just wondering here, but recently when I was under the hood taking a peak at things trying to figure out why my trucks engine shuts off randomly when I shift into neutral and let off the gas, like when I'm sitting at a stoplight or parking.  Sometimes it even does it when I'm rolling into my driveway, essentially any time I shift into neutral.  

This thing has had around 2600$ worth of repairs, new timing belt, new seals, new plugs, wires, cap and rotor etc etc etc.  The only thing that has not been replaced or adjusted is the Accelerator cable.  It never crossed my mind, nor it seems my mechanics mind, but last night when I was under the hood tinkering around I noticed that the cable seems looser than it should be.  Could it be that the cable is too loose and therefore when I let off the gas it shuts the throttle and kills the engine rather than idle properly?

Pics for Reference:
Picture is zoomed in, but there is about an inch or more give and the cable is VERY loose and easy to move around.

[DracoSedentis]

Sorry, double post, but needed to have this picture as well,

When the vehicle is just sitting, no manipulation of gas or running engine, the cable sits like this, attached to the throttle body by the long oval shaped bar.  To me I would think this needs to be tight with the left side against the peg its attached to.  Correct me if I'm wrong, I've done a lot of work on vehicles, but never have I worked on something like this.

[gogmorgo]

That's a bit more slack than I'd be comfortable with, but the "closed" throttle position should be determined by the throttle stop, not the cable. I can't see that causing a dying problem, if anything it would just prevent you from going to wide-open throttle.

I don't know much about the 2.5tbi system, but I would be looking for issues with things like the throttle position sensor or an idle air controller or something like that before looking at mechanical problems.

That said it could be a case of the throttle closing too far, but the throttle stop should prevent that and is one of those things that shouldn't just adjust itself... But that doesn't mean it didn't get adjusted by someone trying to compensate for a vaccuum leak or some other reason.

How clean is the throttle body?

And are you sure that's the throttle cable? The slot in it makes me think it's more likely to be something like a cruise control or auto trans kick-down cable, that wouldn't want to be pulled taught all the time. But I could be wrong there. If it is the throttle cable you should be able to watch it take up the slack while a helper depresses the gas pedal. 

[DracoSedentis]

Well, upon further inspection with some assistance it turns out this is not the throttle cable, that cable is behind this one and is right where it should be in tightness.  The throttle body is pretty clean on the inside as well.  No buildup I can see.  Guess I'll go back to the idle air control and try that.  I had settled on that first a week or 2 ago but decided to take it to the shop that did the work to see if they could find a vacuum leak instead.  They didn't find one, so perhaps this IAC is the culprit. 

 

[HOrnbrod]

Check this - Cruiser Tip #14:

 

14. Restoring throttle butterfly adjustment
 
Okay. Let's start from scratch. First off, that's not an idle adjustment screw. It's a throttle butterfly stop screw. It's purpose is to allow the butterfly to be as close to completely closed as it can be without binding or wearing into the throttle body.
 
It was never intended to be adjusted in the field. But, Uncle Bob didn’t know that, did he?
 
Engine off. Back off the butterfly stop screw with a 3/32” allen wrench until the butterfly is completely closed. Now. turn the screw in until the FAINTEST movement of the butterfly opening is detected. This can be done more easily with the throttle body removed. If you remove the throttle body, be sure to replace the gasket underneath it after thoroughly cleaning the old one off.
 
Revised 07/07/2012

[Ωhm]

2.5L throttle stop will shut down the engine. This adjustment is only so that the throttle plate will not get stuck in the bore. Idle control is a function of the Idle Speed Control Motor (ISCM). Note: the nose of the ISCM is the closed throttle switch (CTS). If CTS fails the ISCM will not operate. Keep in mind that CTS could be good but the ISCM is just bad.

[DracoSedentis]

I'll be looking into these suggestions, I found some other older threads on here about this same engine and same issue that I'm going to look into as well.  On a side note I found out while poking around that this engine, my local parts store lookup system kept telling us that "this vehicle isn't equipped with that part" (IAC).  Found a video of a guy working on a similar issue on good ol' youtube and ended up finding out in my parts store system the part is called an "idle flapper motor''. Found this out after spending a couple hours trying to find diagrams of my engine so I can see it all exploded and named.  Kept finding ones with IAC but could never find one that looked the same as mine.  Corrections and any information is appreciated.   Like I said earlier, I'm great with most things, just never had this type of issue before in any of my other jeeps.

[omega_rugal]

Check the TPS too...