Outer Limits 4x4 Board

Hi my 93 NH is idling at around 2000 rpm and purges a bit any ideas on what might cause this would be appreciated

I'm guessing it "surges" a bit? I was having trouble with erratic idle speed (high, surging, stalling when at lights) which was cured by a good clean of the idle control valve, which goes by a few names - try searching for "idle" and "stepper motor".

Most likle cause is the IDC motor.,

Pull it off and gve it a clean with carby cleaner, otherwise replace