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2021 BMW X3 XDRIVE30I
2.0L I4 Turbo B48•AWD•AUTOMATIC•gas•B48B20•turbo
11 active safety recalls on this vehicle — view recalls
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Repairs0Labor484Torque1486Fluid10DTC2246Battery1Maintenance0Recalls11
P0174high severityPowertrain

System Too Lean Bank 2

on 2021 BMW X3 xDrive30i 2.0L I4 Turbo B48 · AWD

What this code means

The long-term fuel trim for Bank 2 has exceeded the positive limit, indicating lean running on Bank 2.

Symptoms

  • Check Engine Light
  • Rough idle
  • Hesitation
  • Possible misfires

Common causes

  • Vacuum leak Bank 2 side
  • Low fuel pressure
  • Faulty MAF sensor
  • Exhaust leak Bank 2
  • Clogged injector Bank 2

Diagnostic steps

  1. Check fuel trim Bank 2
  2. Smoke test Bank 2 intake
  3. Test fuel pressure
  4. Test MAF sensor
  5. Check for exhaust leaks Bank 2

Repair notes

Same diagnostic approach as P0171 but focused on Bank 2.

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