I have a P0171 code on my 1999 Dodge Dakota Sport 4wd 3.9

Question

Some say to change the o2 upstream sensor so I tried and broke it at the ceramic area but can't get the nut loose - yet. Now I know I have to replace it - do you think that will get check engine light to go out ?

Answer 1

P0171 Fuel trim lean bank 1

Yes the 02 sensor can cause a Bank  to go lean on one side, This can happen when the its signal voltage go bias on the lean side.

Answer 2

P0171 DODGE - Fuel System 1/1 Lean
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