RepairPal Certified shops can diagnose and repair your 1992 Chevrolet S10 Blazer. They provide transparent pricing with a minimum 12-month or 12,000-mile warranty on repairs and services.
First off check for any vacuum leaks. If no vacuum leaks are found, then clean throttle plate area and Idle air contol passage of throttle body with a good carburator or throttle plate spray cleaner.