Cadillac XT5 2014 Check engine light P0171 lean mixture
Cadillac XT5 2014 check engine light on with P0171 lean bank 1 code. Rough idle and slightly worse fuel economy noticed. 130718 km. This fault code is stored when the engine control unit detects a specific fault condition. Common causes include sensor failures, wiring faults, and component wear. Always read additional fault codes before replacing parts — multiple codes together provide a clearer diagnosis. Clear the code after repair and test drive to confirm the fault does not return.
🔍 Symptoms
⚙️ Possible Causes
Repair / Solution
Based on 102 driver confirmations
⚠️ Wrong Diagnosis?
No commonly reported misdiagnoses for this fault yet. If you have replaced a part that did not fix this 2014 problem, submit a wrong diagnosis report — it helps other drivers avoid the same costly mistake.
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