'99 Dakota w/ 3.9 won't idle....

My sons Dak won't idle. I can raise the idle w/ the gas pedal and drive it. What do I look for? If it was a 'yota I would know the idle air control valve was sticking- does the Dak have something similar? Thanks.


Tim

I would take the iac motor out and clean it and the passaage out with carb cleaner or equiv. It's on throttle body, and should have 4 wires in the connector.

A few years ago my '96 Dak 3.9 had the same symptons. Pulled the IAC valve, cleaned it & it's passage, ran like a top afterwords.
It was on the backside of my throttle body, IIRC.

yeah i have to agree. thatd be the first suspect.

agree with everyone else just when you clean it becareful not to touch the plunger or you could break it. I usually take the IAC out and just spray it with carb cleaner, let it sit for a couple minutes then put it back in. No not touch it or wipe off the carbon.

???? The plunger is made of steel...Go ahead and clean away... The hole point of removing it is to remove carbon from the passages and the IAC. Cleaned tons of them that way.

Don't laugh, but my 97 would take spells it wouldn't idle. One night it wouldn't start, cables were funky looking, not corroded but just funny looking, cleaned them and it starts better, and the idle situation went away also.

Mine's IAC went bad right after I got it, it wouldn't idle steady, but never died

???? The plunger is made of steel...Go ahead and clean away... The hole point of removing it is to remove carbon from the passages and the IAC. Cleaned tons of them that way.

todd you are correct, however there is electronics behind the plunger and pushing in and out on the plunger too hard could cause damage to the electronics thus destroying the IAC.

There's no need to push and pull on the plunger to clean it. Some cleaner and a small brush works just fine. Idle strategies will have to relearn due to increased airflow.

Might also be a weak battery.

My father's 98' 5.2L Durango wouldn't idle either; it would just spit and sputter until you pressed the throttle down a little ways and then it would even right out. Turned out to the throttle position sensor.

Cleaned the ISC valve last night (and the battery terminals, just to be safe ) and the warm idle was smoother. It idled fine this morning on cold start. Thanks, guys.


Tim