I am trying to tack down idle surge issues. The idle has randomly been staying up or jumping up (one time at almost 3k). I know these cars have an IAC issue and there are restrictor plates out. I have one and it didn't really change this issue. I also feel hesitation when driving. I pulled the IAC and it drove much better (but needed to be careful not to stall it, it idles at about 650 with it unplugged and can dip when slowing down). I have done quite a bit already on this: * New MAF (one of the screws was stripped out, only leaving one screw). * New air filter * cleaned throttle body (these throttle bodies look pretty bad after 75k I would say). Or at least mine does * Checked tps (showing .96 dc volts and goes past 4.5 at WOT) * I disconnect the battery to reset idle controls and let it run for a while (everything off), then for a while with everything on. * The IAC looks fairly new (I am the 3rd owner). But cleaned anyway. * But... when I pull the IAC when acting up, it goes to 650 and behaves. So I believe the IAC is at least the symptom, but I don't know if it is the cause (but looking likely). I am trying not to just guess with new parts. Any way to actually test the IAC? Otherwise I am thinking new IAC, and if not that, throttle body. But starts to add up if I am wrong. Thanks.