idle adjustment for dummies?
 

hey im new to this whole deal and just started learnin about the diesel world a couple years ago (and im a slow learner). but, when i bought my truck it was bone stock with 100k on it and it has always idled just a little high like 850 or 900 usually. since ive owned the truck i learned about lift pumps and injection pumps the hard way and they have both been replaced, so my injection pump is ruled out on making it idle high. i also took it to my local dodge dealership and they claimed to just adjust the idle on the apps. i didnt like this idea because it has a sticker right on it that says "do not adjust". so the mechanic says its no big deal start the truck up and he'll adjust it for free. so next thing ya know this didnt even turn my idle down and i was throwin check engine codes all the time. well i replaced my apps and dont throw check engine codes anymore but i still have a slightly high idle and have ruled out injection pump, and apps and dont know what else it could be. any help would be appreciated. also anyone know where i could get my truck on a dyno around here? (central ohio)

Yaknow I have never heard of anyone with idle issues so this is a wierd first for me

there is no way to adjust the idle as far as I know

I thought idle speed was controlled by the injector pump electronics. Don't know this to be the case for fact. Never heard of idle being adjustable on the 24V though.

If Im not mistaken the idle is controlled by the ECM and there is no way to adjust it.

BTW, dont let the moron "mechanics" at Dodge get their hands on your truck. Youre better off working on it yourself.

yeah i'm with these guys. don't believe there to be any adjustment. is it idling at that speed in neutral or in gear? if it's idling in neutral/park at 900 that's pretty good actually.

AMEN to that!!!

it's been years ago, but i had a simple problem 300 miles from the warehouse.
a cracked fuel return line was leaking fuel, enough that it must have been spraying the windshelds of the cars behind me, somebody kind of waived at me to pull-off the road... sure enough their was a steady stream of fuel that i was loosing.....
i then went to a near by dodge dealer, for the repairs....
they ordered the part from another dodge dealer and said that they would have me fixed up by 5:00 PM....... the other dealer sent the wrong parts twice.....i ended up having to stay in a motel for 2 nights!!!!
never got the right return tubing part, then had to force the mechanic to repair it with rubber tubing. they charged a fortune for their stupidity and caused me to loose about 3 days of work.....

I don't think the idle can be adjusted outside of the IP. My own experience the idle acted only very slightly slower, maybe 25 rpm and only measureable with a scanner shortly before the IP went out in the middle of no where. After replacing the IP the idle was a bit faster than original but after about a month it slowed down to normal and has remain rock steady since.I'm not even sure it can be internally adjusted as the software reads crank position and time so it is more or less preset by software. Mis matched injector pop pressure will make the idle a bit rough but not necessarily change speed.

your truck is idling at the correct rpm if it is in park or neutral. if it idles at 900 in gear, than there is a problem.

i will get back with you guys today on what the exact idle is when it is in gear and what it is in park/neutral. i haven't been driving it because i just put my turbo on last week and it blew part of the intake manifold cover gasket out the side. so major boost leak. my parts are supposed to be in today so i will fix it and put my rpm's on here later tonight.

alright she idles between 800 and 850 in gear and between 900 and 950 in neutral/park. is that normal? because it really seems like mine idles higher than everyone else's trucks.