p0171
Moderate
Nissan · SUVs
System Too Lean (Bank 1)
Quick Answer
Error code P0171 on your Nissan SUVs means: System Too Lean (Bank 1). This is usually fixable — see the step-by-step guide below.
Affected Models
Likely Causes
  1. Faulty oxygen sensor
  2. Fuel pressure regulator malfunction
  3. Leaking fuel injectors
  4. Air leak in intake manifold
  5. Defective mass airflow sensor
How to Fix It
1
Connect OBD-II scanner to vehicle
2
Check fuel pressure readings
3
Inspect oxygen sensors for proper operation
4
Test mass airflow sensor readings
5
Inspect intake manifold for leaks
Pro Tip
This fix requires some technical knowledge. If you're unsure about any step, consider contacting support or a qualified technician.
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