I have a similar problem -- idle is about 1500 RPM. When I spray carb cleaner where the butterfly pivot rod exits the throttle body on the right (passenger) side, the idle drops drastically and becomes very lumpy, so I assume the bushing is badly worn.
Question: is there either a replaceable bushing in the throttle body, or possibly is there a seal? My fear is that my only option is replacing the throttle body.
Thank you in advance, Parkerea