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Discussion Starter #1
hi
Have a 96 Ram2500 that has served me very well. All stock - no fancy add on's.
However, i have a rather annoying problem with my idle.
I have replace the throttle cable and the return spring, also the intake air temp device (analog device where resistance varies with air temperature).
But the idle varies! Set at 750, it varies from cutting out to reving at 1200.

Sometimes i idle so low that when i put it in reverse, it dies. This happens especially in the summer. It seems to lessen somewhat when i put in some Lucas treatment.

Now, between 15-50 degrees F, when i first crank it up, i start at the 750 RPM range [while still cold], and then when i go drive around, AFTER it gets up to temperature, I'm idling at 1200...cannot get it to go back down (except get out, raise hood, and "bottom out"[move to resting position] the throttle rod.

Right now i'm lost to a solution.
Any ideas?...I'm either wearing my brakes out, or dying in reverse!!
thanks
 

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Are you adjusting your idle with the adjustment screw on the injection pump?
 

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Thanks for responding.

I have NOT adjusted my idle. This is because sometimes my idle is high (like now), whereas other times it is low (engine cuts off when put in reverse).

I know it's weird. And even weirder is that it seems ambient temperature dependant (which is why i replaced the air intake sensor).

In the summer I suffer from an idle too low. Now in 15 to 50 degree winter time, my idle speed is 1200+. strange i know.

I'm afraid to adjust the idle (via the low idle adjusting screw on the injector pump) because i feel that on a warmer day the idle will not "stay" there.

The only way i can get the idle to behave (stay in range) is to raise the hood and grab the throttle-lever-to-injection-pump-linkage-rod and gently bottom it out (just move it to it's end of travel). Then RPM's are fine. But if then close the hood, get back in and tap the accelerator, then the idle will return to its previous level. That's why i replaced the throttle return spring - i wrongly assumed the stronger spring would pull the throttle-lever-to-injection-pump-linkage-rod back to the end-of-travel position (as i had done manually), and i would get my ideal idle.
 

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The first thing to do is check the spring that pulls the throttle rod. It looks like one spring but is actually two springs wound together. There should be two hooks on each end. If one is broken and missing then the spring is half as strong as it should be so it can't pull the throttle lever on the pump against the stop like it should. This is a common problem. If there is no spring at all then you are depending on the throttle lever to return to the stop with much less strength than it needs. There may be a safety recall about the throttle linkage for your truck. You can enter your VIN on this site Dodge - Contact Us to find out if there are any safety recalls that have not been done on your truck. A safety recall is free.
 

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Discussion Starter #5
Thanks for the reply Mr. G.

several things;

1) Replaced the spring that pulls the throttle rod. The old one was not broken, but i replaced it with a stronger spring to insure it would pull the throttle rod back.

2) Replaced throttle cable. I looked up the recall info (thanks for that link) and they did have a recall on the throttle cable and some control linkage joints. Several years back I replaced that myself, cause i didn't trust the local dealer to even rotate tires, much less do actual work on the engine. Anyway. But all that was years ago, and has been working since.

So now;
3) Cranked up.
a) when cold, would idle at 500-750.
b)after warm, would idle at 1000-1200.

4) only way to get idle down again, would be to
a) cut off engine
b)press accel pedal, suddenly let off, making it "slap" back into it's original position
c) crank back up, idle at 500-750

5) again, if then drive around, idle will return to 1000-1200.

Any ideas?
 
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