Gasoline Engines

Idle speed is controlled by Powertrain Control Module (PCM) and is not adjustable. If engine idle concerns are present, check for contaminated fuel, vacuum leaks and incorrect ignition timing. Ensure throttle bore, EGR system and PCV system are clean. If these are okay, check PCM for Diagnostic Trouble Codes (DTCs). See SELF-DIAGNOSTICS - EEC-V (GASOLINE) article. If no DTCs exist, go to TROUBLE SHOOTING - NO CODES - EEC-V (GASOLINE) article.