High idle problem.....

[Cbailey8971]

This just started with no ac on or def. on start up idles at 1200 rpm ,after warm up idles at 1000 then let sit for 15-25 sec then it will slowly drop to 600-700 . If I rev it it might stay at 1500 -1700 and stay. If I shut it off and restart it will go to normal. What is going on any idea?? Any help would be appreciated. Chris

 

[oldcolt]

Clean your IAC valve.....it is probably gummed up.

 

[Cbailey8971]

Ok this may sound stupid but what and where is the iac valve?

 

[Cbailey8971]

Oh and by the way it has 40,000 miles on it

 

[VENOMOUS1 RACING]

On the intake on passenger side below TPS throttle position sensor. TPS is likely at fault, but clean iac first.

 

[Cbailey8971]

Ok cleaned the iac still doing it. Is it easy to change the tps?

 

[Cbailey8971]

If not can you explain?

 

[Cbailey8971]

Another weird thing I was reading another post ... Guy said it happened when he got caught In a hard rain and it happened to me after a hard rain too.... ??

 

[VENOMOUS1 RACING]

TPS for sure! About $20 at autozone. Two torx-25 screws and remove. You'll notice it's under tension by spring inside TPS. You'll have to insert new one, then rotate to have it sprung back under tension and to align screw holes.

 

[Cbailey8971]

Little confused . Do I rotate tps with spring in it? How many times should I rotate it? And is there any learning or other procedure I need to do. Sorry it's my first 8.3

 

[Cbailey8971]

Or is it as simple as bolting it on?

 

[VENOMOUS1 RACING]

It's easy, it only rotates an 1/8 turn if that. Note how the old one comes out. Very simple and no relearn process

 

[CaptnCrash]

Do you have a stock TB or a 3rd party one ?

 

[VENOMOUS1 RACING]

Do you have a stock TB or a 3rd party one ?

I don't believe i do but I'll look.

 

[ViperPete]

For those that do not know the acronym for IAC it is Idle Air Control.

It controls how your truck idles.

It is probably gummed up.

 

[triblk6spd]

Just an addition in case anyone finds this thread looking to cure a high idle problem.
Same problem...in had *at first a high idle intermittently then it started idling high all the time. ..so I first removed and cleaned the entire IAC and IAC opening in the intake and also lightly lubricated the unit itsself. No help. Next in replaced the $20 TPS sensor. No help. Finally bought a new $170 IAC and BAM problem solved. Yes it would have been nice to just magically fix the issue but not the case with me.

 

[earl lee]

Just an addition in case anyone finds this thread looking to cure a high idle problem.
Same problem...in had *at first a high idle intermittently then it started idling high all the time. ..so I first removed and cleaned the entire IAC and IAC opening in the intake and also lightly lubricated the unit itsself. No help. Next in replaced the $20 TPS sensor. No help. Finally bought a new $170 IAC and BAM problem solved. Yes it would have been nice to just magically fix the issue but not the case with me.

Actually, I just had this happen to me also. My IAC was dirty, I cleaned it up and stuck it back in but it would still idle high and get stuck. I read you have to disconnect the battery to make the truck learn again. So I disconnected the battery and its been fine for 3 weeks now. If it starts acting up again, I'll just buy another IAC.

Did you disconnect your battery?

 

[mopar-or-no-car]

For those that do not know the acronym for IAC it is Idle Air Control.

It controls how your truck idles.

It is probably gummed up.

Wisdom from the guy who tried to remove his throttle shaft with the blades still on...LOL

 

[VENOMOUS1 RACING]

Wisdom from the guy who tried to remove his throttle shaft with the blades still on...LOL

C'mon now, he's still innocent until proven guilty. Although his lack of return posts, pics of throttle body with screws and blades in tact, and a damaged blade are evidence of guilt.

 

[VPRPWRD]

We have all done dumb stuff. Cut him some slack.