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Preparation For Checks

  1. Frequency valve is operated by pulsating voltage from ECU. By measuring this signal, mixture function of system can be tested and changed. A high-quality dwell meter is used to check and adjust frequency valve control and duty cycle.
  2. Connect tachometer and oil temperature gauge. Ensure A/C is off and transmission lever is in Park. Throttle valve lever must be against idle stop. Accelerator Bowden cable must be tension free at throttle lever. Adjust if necessary. Engine oil must be at operating temperature of 176°F (80° C). Check and adjust idle speed if necessary.
  3. Connect dwell meter to 2-wire testing connector. Connector (Blue/White wire) is behind throttle valve housing.
  4. The color-coded wire should be connected to positive (+) lead of dwell meter. Other wire in connector is ground and should be connected to negative (-) lead of dwell meter. Set dwell meter on 4-cylinder scale. Start engine and run until warm.
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