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
P0396
Cylinder pressure sensor, cylinder 1 circuit range/performance
Generic
Ignition System
High severity
P0399
Cylinder pressure sensor, cylinder 1 circuit intermittent/erratic
Generic
Ignition System
High severity
P0400
Exhaust Gas Recirculation Flow Malfunction
Generic
Auxiliary Emissions Control
Medium severity
P0402
Exhaust Gas Recirculation Flow Excessive Detected
Generic
Auxiliary Emissions Control
Medium severity
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