High idle

Hi my 87 jeep cherokee is going into high idle again. it sometimes idles at 2000 rpms as opposed to 500. Is the tps the only thing that will correct this. I changed it last year and it helped a lot. it has just started up again this week, and i hope i don't have to replace it again. thanks
matt

oh yeah

its a 4 liter sorry

Possible candidates:
1. Idle Air Solenoid- Clean it before considering replacement
2. Throttle body gunked from oil inhaled caused by a stopped up CCV tube. Clean the throttle body if it is black inside the bore. If it is black, remove CCV tube and clean and clean CCV gromet in valve cover.
3. Vaccum leak-trace out those plastic vac. lines

Do a search. You're not the only one.

Cleaning the throttle body and the IAS eliminated my problem with high idle.