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Component Tests and General Diagnostics

SYSTEM INSPECTION

NOTE: Troubleshoot with the Self-Diagnosis Checker before performing the following steps.

1. Warm up the engine and run it at idle.

Checking Dwell:





2. Connect a dwellmeter to the check connector (White:1-pin), and note the dwellmeter reading.
3. If the dwellmeter reading is fixed at 0°, check the following:
a. Ignition pulse signal for the engine control unit.
b. Characteristics of the vacuum sensor.
c. Characteristics of the water thermosensor.
4. If the dwellmeter reading is fixed at 27°, check the following:
a. Characteristics of the intake air thermosensor.
b. Vacuum hose routing.
c. Oxygen sensor.
5. If the dwellmeter reading is fixed at 36°, check the characteristics of the water thermosensor.

Dwell Range:





6. If the dwellmeter reading is fluctuating out of the 20°-70° range, check the following:
a. Vacuum hose routing.
b. Oxygen sensor.
c. Air/Fuel solenoid valve and wiring harness.
d. Clogged jets and air bleeds in the carburetor.

NOTE: If all these items are in good working condition, adjust the idle mixture (duty) with mixture adjusting screw.