If you have the Quadrajet carb the high idle screw is located under the vacuum pot,remove the pot and you will see the high idle screwLets see if this link on a similar question helps.
High idle problem
I have a 83 Cutlass Supreme with a 307,in the morning when I warm it up it will idle normal but after about 5 mins when it's warmed up it will idle high and I have to tap the gas and then it will idle normal, my question is why does it do that and how to I fix that?gbodyforum.com
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