Strange Idle problems

[Wizard50369]

I had a little noticable idle surge (idle would be around 1200 and move +/-50 rpm). So I read the little thing on how to fix the idle surge. First step, clean TB. After i do this and reinstall the car idles at 1600. Most of the time after driving around and stopping at a light it will climb to 2000. The idle surge is way more noticable now, not to mention annoying. I checked the BISS and I dont have one! Someone decided to use a hex bolt with tape around it. Bastards. Aslo after i drive around, than shut the car off and turn it back on, it idles down at like 500 rpm. Up and down between there and 700. Any ideas on what this could be?