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Idle Speed

CAUTION: Some tachometers may not be compatible with ignition system. Consult tachometer manufacturer before connecting tachometer to system. DO NOT  allow tachometer terminal to become grounded, or ignitor and/or coil may be damaged.
NOTE: Idle speed is controlled by the ECM and is not adjustable. Check idle speed with air cleaner installed, all air intake system hoses and vacuum lines connected, electronic fuel injection system wiring connectors tight, transmission/transaxle in Neutral, A/C and all accessories off and engine at normal operating temperature.
  1. Connect scan tool to Data Link Connector (DLC) No. 3. See Figure. Scan tool is used to read engine RPM. Apply parking brake. Place transmission/transaxle in Neutral. Start engine and maintain engine at 2500 RPM for 90 seconds and then allow engine to idle.
  2. Ensure idle speed is 650-750 RPM. If idle speed is not 650-750 RPM, check Idle Air Control (IAC) valve, wiring and Electronic Control Module (ECM). See IDLE CONTROL SYSTEM in SYSTEM/COMPONENT TESTS article. Remove scan tool.
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