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Idle Mixture

NOTE: Idle mixture must be checked with air cleaner installed, all air intake system hoses and vacuum lines connected, EFI system wiring connectors tight, transmission/transaxle in Neutral, all accessories and cooling fan off (if equipped) and engine at normal operating temperature.
  1. Ensure idle speed is within specification. Install jumper wire between proper terminals of check engine connector. Connect positive (+) probe of voltmeter to terminal "VF" or "VF1" and negative (-) probe to terminal "E1". See Figure.
  2. Start engine and maintain engine RPM at 2500 RPM for approximately 2 seconds. With engine RPM at 2500, count the amount of times that voltmeter fluctuates between the specified voltage. See IDLE MIXTURE TEST SPECIFICATIONS TABLE.
  3. If the amount of fluctuations is less than the minimum amount, check for air leaks at the air induction system, defective airflow meter or throttle body.
  4. If fluctuations were within specification, accelerate and hold engine at 2500 RPM for approximately 2 minutes. Install exhaust gas analyzer probe in tailpipe at least 1.3 feet. Wait one minute and check idle mixture readings. If readings are not within specification, see IDLE MIXTURE TROUBLE SHOOTING TABLE.
IDLE MIXTURE TEST SPECIFICATIONS

Voltage Minimum Fluctuations
0-5 8 Per 10 Seconds
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