My '90 Deville with 123K runs great (better low end punch than my NorthStar) but I have a couple funky idle problems. When you slow to a stop sign, it seems like curb idle doesn't occur till after you stop. What gives with this? Also, it "hunts" 3 or 4 times for curb idle before it settles down. Idle Speed Control motor is fairly new. Would it be worthwhile to check Throttle Position Sensor setting? Thanks for your help!