p0171
Moderate
Lexus · SUVs
System Too Lean (Bank 1)
Quick Answer
Error code P0171 on your Lexus SUVs means: System Too Lean (Bank 1). This is usually fixable — see the step-by-step guide below.
Affected Models
Likely Causes
How to Fix It
1
Connect OBD-II scanner and read fault code
2
Inspect fuel pressure using fuel pressure gauge
3
Test oxygen sensor voltage output with multimeter
4
Check for vacuum leaks using smoke test
5
Clean or replace fuel injectors as needed
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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