EEC-V Models

NOTE: Idle speed is controlled by Powertrain Control Module (PCM) and is not adjustable. Idle speed specifications are for reference purposes only. 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 appropriate article:

For 4.0L vehicles, see TESTS W/CODES .
For 5.0L vehicles, see TESTS W/CODES .
If no DTCs exist, go to TESTS W/O CODES article.

Turn off all accessories before checking idle speed. Ensure cooling system is filled to correct level. Ensure there are no vacuum leaks or unmetered air entering the throttle chamber on mass airflow design systems. If vehicle is equipped with electric cooling fan, check idle speed when fan is off. For engine idle specification see IDLE RPM SPECIFICATION table (EEC-V).

IDLE RPM SPECIFICATION (EEC-V)

Application

⁽¹⁾⁽²⁾ RPM

4.0L OHV & OHC, 5.0L

725-775

⁽¹⁾	Idle speed is checked with engine warm and all accessories and fan off.

⁽²⁾	Idle speed is computer controlled and is not adjustable.