Idle Speed & Ignition Timing

Idle mixture is controlled by Engine Control Module (ECM). Idle speed is preset by manufacturer and is not adjustable. Vehicle is equipped with an electronic computer-controlled ignition system. Timing is not adjustable. For operation, specifications and adjustments, see THEORY & OPERATION - 2.2L ION , SERVICE & ADJUSTMENT SPECIFICATIONS - ION & SATURN "L" SERIES and ON-VEHICLE ADJUSTMENTS - CARS articles.