OBD fault code library
Look up any P or U code to see what it means, what causes it, the parts involved and how it gets fixed.
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Fault codes
P1407
EGR Air Intrusion in Exhaust Supply to EGR Valve
Chevrolet
Auxiliary Emissions Control
Medium severity
P1420
Intake Air Low Pressure Switch Circuit Low Voltage
Chevrolet
Auxiliary Emissions Control
Medium severity
P1421
Intake Air Low Pressure Switch Circuit High Voltage
Chevrolet
Auxiliary Emissions Control
Medium severity
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