p0171
Moderate
Lexus · Sedans
System Too Lean (Bank 1)
Quick Answer
Error code P0171 on your Lexus Sedans 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 to vehicle
2
Record freeze frame data
3
Inspect vacuum hoses and connections
4
Test fuel pressure with gauge
5
Clean or replace fuel injectors
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
New vacuum hoses
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