Broken Idle Spring?
 

Hi, I just picked up a 97 2500 4x4 with a 5spd. I drove the truck home, let it sit overnight and went to start in the am. The truck would not start without any throttle applied and once started it would not idle. I looked around under the hood and found a small spring (thats attached to throttle cable bracket and throttle arm) had broken. Had a friend start the truck and keep it running while i messed with the throttle arm. Found that upwards pressure on the arm let the truck idle. So I went to the auto parts store and picked up some assorted springs, found one that had similaighwayr tension (approx) and hooked it up. The truck starts, only with throttle applied, but it idles on its own. What exactly does this spring do? Whats the name for it? And how important is it to have a proper tension spring on this? Also just did a new fuel filter, oil change, and air filter on this truck and it got 13.9mpg mix city/hwy. Was wondering why mileage is so low, possible due to this spring, or something else? Oh btw truck has 162,xxx miles k&n filter and 5 inch stacks on it. Thanks for your help.

not sure on the spring, but you should be seeing better milage. especially with a 5spd. i get around 18 city/highway with all the mods in my sig, and i have a bad driving habbit. always in the pedal. im sure a few more knoweldgable guys will chime in soon:w2:

ya i get bout 20 and my foot aint the lightest. i personally don't like the k&n filters but it's personally opinion. and when that spring would wear out on mine it'd always shoot the rpms through the roof everytime i hit the throttle.

Oh also i noticed that the water temp goes from 140 creeps up to 190 and then drops back down to 140 in seconds. Could this be a thermostat or possibly a bad fan clutch? How would I go about diagnosing a fan clutch with out losing a few fingers?

The temp-fluctuations are normal. Pretty much everybodies 12v on this board does this.
As far as bad mileage, my cummins got BARELY 16mpg on the highway driving a very consistant 71mph.


When I first bought the truck, with a 3 year old fuel filter and air filter, and stock intake/exhaust etc, I drove home going 80-85mph and got 19.33 mpg the whole way. I'd love to know why I am getting terrible mileage.

As far as your mileage, what gears does it have? Mine has 3.55 and I get 18-19 mixed city and highway and quick to the speed limit of the road I'm on. Tension shouldn't matter. :c:

My truck has 355's, but my motor also blew the other night. Pretty sure I had some big issues to cause my poor mileage.

the tag under the hood says 3.55. As far as that spring goes i picked one up from dodge for less than 3 bucks. Also my truck seems to idle very low, tach reads 450. The truck seems to run fine, once i warm it up enough to stay running.

also dont forget to see if the recall for the throttle cable was done yet

It might be called a throttle return spring, but I'm not sure.

When I had the throttle cable replaced on mine, they told me that the return spring was weak and they had to put in a new one. I felt something give while I was driving. As in the pedal all of a sudden felt very spongy. I knew the cable recall wasn't done yet, so I took it to the dealership not long after.

Repair didn't cost me a penny, because of the recall. This was about 4 months ago.... I did have to wait about 3 hours, though.