p0171
Moderate
Cadillac · SUVs
System Too Lean (Bank 1)
Quick Answer
Error code P0171 on your Cadillac SUVs means: System Too Lean (Bank 1). This is usually fixable — see the step-by-step guide below.
Affected Models
Applies to all models
Likely Causes
How to Fix It
1
Connect OBD2 scanner to diagnose the code
2
Check oxygen sensor voltage readings
3
Inspect fuel injectors and vacuum lines
4
Clear the code and test drive
Pro Tip
This fix requires some technical knowledge. If you're unsure about any step, consider contacting support or a qualified technician.
Parts You May Need
Oxygen sensor
Fuel injector cleaner
Diagnostic tool
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