Weird Idle...
 

Ok guys, I'm not new to cars, jeeps yes. I have a 2000 Jeep xj sport 4x4 I6 with about 138K miles on it. I do not know any past maintenance on the truck so I'm not sure where to start with this. I am having the same problem as this guy is in the video-
https://www.youtube.com/watch?v=X5FRFsGpuTo

It almost idles rough, but its not bad. I have NO hesitation and I'm getting roughly 18MPG on the highway which isn't too far off from the normal. In the video he says his problem was the ignition coil but couldn't it also be spark plugs or would it be more noticeable of a misfire? Should I start by replacing the plugs?

PLEASE, school me on all this. I love to learn so yea. I wanna keep this jeep running for the rest of my life!

Thanks,
David

"It almost idles rough"

It's a straight six, not a V-6 or 8 so some vibration is to be expected. If you have any doubts about the health of the motor the first place to start would be a compression or better yet a cylinder leak down test and go from there.

If the motor itself wobbles around chances are real good the mounts are rotted and need to be replaced.

I would start with maintenance, since you don't know whats been done. Do it now so you know :) I would do plugs, oil change, check other fluids.

Turbo- Yea, I was just thinking that, my blazer idle'd sorta like this but it had a misfire, but with that, I could feel with while cruising this, I cannot. motor mounts look good to me, but I'll check them again in the morning.

Jeepki- I guess I worded that wrong, I changed the oil, checked all the rest of the fluids and they looked good. It sounded like I just bought it and drove it lol, hell no. I got it and went over it all.

oh ok lol, yeah I thought maybe you had it a day or two. well I have seen rust build up in the fuel rail before, causing a non-smooth idle. Just poped it off and cleaned it with carb cleaner.

hmm, ok, I already cleaned the throttle body and ran some fuel treatment through it, I'll check all these things!