RepairPal Certified shops can diagnose and repair your 1992 Dodge D150. They provide transparent pricing with a minimum 12-month or 12,000-mile warranty on repairs and services.
Best to inspect why this is happening, you may have a vacuum leak, bad oxygen sensor, sticking EGR valve etc, and the idle air motor is 'chasing' meaning it is trying to keep the idle with in spec, but other factors are interfering.