Kia 96 seems to be jacking at idle stage

what do I need to check or replace to make it run smooth

I don’t even know what “jacking” means.

What model is it? How many miles? Tranny? Maintenance history (especially recent)? What in tarnation does “jacking” mean?

We need something to work with here.

“Jacking”–as in raising the car on the device that is used when you change a tire??

Somehow, I think that there is some terminology being used here that is not translating very well. First of all, I have to assume that you are trying to tell us about a problem with your engine. Am I correct? If so, then try describing exactly what the engine is doing, and when it is doing it (when first started, after it is warm, in gear, out of gear), how long it has been since you had the spark plugs, air filter, fuel filter, and PCV valve changed, how long ago that the transmission fluid was changed, and how long the Check Engine Light has been illuminated.

Like the police department whose toilet was stolen, we have nothing to go on right now.

I thought “jacking” meant taking the car at gunpoint.

poss this guy has an aircraft,and he’s telling us he’s been hijacked??? I recommend he just lets the car down and goes to a garage.