Their is no Lexus category so im posting this under Toyota. about 2 weeks ago i purchased a 1993 Lexus sc400. I am having a problem with the idle. when i first start it up when it is cold, it will idle between 1100 and 1300 rpm, but as soon as the needle comes up on the temp gauge, it starts to rev up and down between 1100 and 2000 rpm. I have a lot of plans for this car but i don't want to start putting money into it until i figure out the problem. I've been told told many things, but the main thing i have been told is its the idle air control valve so last night i took it apart and it turns out the bearings on it were all sticking so i cleaned em and loosened them up but it didn't help at all. Please Please help me!