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Checking Load Sensor

  1. Connect adjustable timing light or TDC sensor system to engine. Set tester to 4-cylinder scale. Accelerate engine to 4000 RPM.
  2. Ignition timing should be 42° BTDC. Pull off vacuum hose on EZF control unit. Ignition timing should be 20° BTDC.
  3. If ignition timing of 40° BTDC cannot be reached, build up approximately 7.25 in. Hg vacuum directly to control unit with a vacuum pump. If there's no change in ignition timing, replace EZF control unit. If ignition timing changes, check vacuum line to intake air distributor for leaks.
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