Extremely high and rough idle

Hey guys I need some help with my high idle. I've got a 1988 Cherokee with nearly 220,000 miles on it and it idles extremely high. It idles high enough sometimes while I'm driving that it will accelerate on it's own to 40-50 mph without me even touching the gas pedal. This of course is extremely dangerous especially when I have to make a sudden stop. I have replaced the cap, rotor, plugs, and cleaned the throttle body and it has only helped a little. I do have the Rusty's K&N Intake on it and I've noticed that some of the vaccum line connections are very tight. Could that have anything to do with my high idle? Also, to my knowledge, the 02 sensor and TPS have never been replaced so I'm guessing at 220k that its time for a change...

Pull the major vacuum lines off of your intake and plug them with your finger. See what happens. The vacuum line running from the intake to the vacuum canister (behind right front fender) when broken/disconnected can give you an idle of 1200-1500 or so.
Some other things to look at are TPS, the TB butterfly spring and a sticky IAC. Bit I doubt an IAC stuck all the way open will idle that high, but I've never tried it to see. I had one TPS that had an internal problem, it would short at about 1/3 throttle. You could see it with a analogue ohm tester, the needle would jump when the throttle was in a certain position.
My IAC is clean but still sticks occasionally, a periodic squirt of penetrating oil will keep it happy for a month or so.
Wife had an issue with the carpet getting wadded up under the pedal, that would occasionally cause a high idle. I trimmed it well away.
Also possible the throttle cable is sticking, if a few strands have frayed they will cause hitches in the operation.
Just a few ideas, what you have is really dangerous, especially if you have an automatic.

Don't forget to check the vacuum booster for the brakes. For your idle to be that high you need a fairly large vacuum leak.