obd1 code 51 51 air/fuel at limit. What are the possible causes?

1994 CHRYSLER 300
130,000 MILES
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DALESWENSON
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I changed the oxygen sensor about two years ago and it seemed to fix it for awhile. It's starting to run rough especially when cold.
Mar 18, 2012 at 8:56 PM
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JACOBANDNICKOLAS
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I am showing a code 51 is a lean system. Check for vacuum leaks.
Mar 18, 2012 at 9:05 PM
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RASMATAZ
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  • ASE Certified Mechanic
You need to inspect and test again the O2 sensor-
Mar 18, 2012 at 9:08 PM
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