Ford OBD codes
Search Ford fault-code guides when you want the generic OBD-II definition with notes that are a little closer to common Ford fault patterns.
Showing 4 sample guides. Refresh to rotate the mix.
P0300
P0300 usually means the engine is detecting random or multiple-cylinder misfires.
On many Ford engines, coil, plug, or intake-leak issues are still the first places to look.
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P0171
P0171 usually means bank 1 is running too lean.
On many Ford engines, vacuum leaks and PCV-related air leaks move very high on the list.
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P0420
P0420 usually means the catalytic converter efficiency is below the threshold the ECU expects.
Ford-specific exhaust leaks, sensor bias, or a tired converter can all sit behind P0420.
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P0455
P0455 usually means the EVAP system has detected a large leak.
On Ford vehicles, cap sealing, vent plumbing, or EVAP hose faults are all common places to start.
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