91 405 dl 87k miles white 4 door used to sit at 2200 for 5 minutes and slowly come down to 1400 after 15 mins....finally, someone was able to fix it by: 1) cleaning out the idle control valve with brake cleaner spray 2) adjusting the idle screw in front by the radiator, it was set too high. it has to be set just right he said because there is a small valve below the screw? anyways, this time we didnt touch the computer and he said all the readings were good before he started..
