Mike's Workshop Manuals
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2003
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Century Base
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Engine Controls Self-Diagnostics - 3.1L Engine
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Diagnostic Tests
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DTC P1404: EGR Closed Position Performance
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Conditions For Running Test
Conditions For Running Test
The engine is running.
The Ignition 1 Signal voltage parameter is 11-18 volts.
The EGR valve is commanded to zero percent for 20 seconds after the EGR valve has been commanded to open more than 40 percent for 0.5 second.