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Home >> Chevrolet >> 1999 >> Astro Van 2WD V6-4.3L VIN W >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Relays and Modules - Computers and Control Systems >> Engine Control Module >> Description and Operation >> System Diagnostics
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System Diagnostics

The system diagnostics are tests that monitor and evaluate a particular emissions system and the effect that system has on vehicle emissions. The system diagnostics consist of the following:
^ The Catalyst Monitor diagnostic tests.
^ The Misfire Monitor diagnostic tests.
^ The Fuel Trim System diagnostic tests.
^ The Evaporative (EVAP) System diagnostic tests.
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