what do i do if it say system too lean(bank 1 ) on 1997 Ford F-150

what to do if it say system too lean (bank 1 )

Asked by for the 1997 Ford F-150
You take it to a shop where a confident technician could diagnose a lean condition which could be caused by quite few different things.

1 more answer
Its more likely the Oxygen sensor #1. There are other parts that mimic that symptom, but usually is the OS.
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