85 Seville Idle Wanders

My 85 Seville 4100's Idle Wanders About. It Will Go Real High, Back Down To Less Than Normal, And Then Race Again. It Will Do This For A Couple Of Minutes Until On One Of The Low Idle Cycles, It Stalls. I've Heard Egr, Oxy Sensor, Vacuum Leak, What Do You Guys Think.

First thing I'd do is clean the throttle bores and plates with some spray carb cleaner and a toothbrush.

There also is a thing you can buy to hold the idle in place. My family's Wagoneer has that.

Check this thread 6 months old, dead.