p0171
Moderate
Toyota · SUVs
System Too Lean Bank 1
Quick Answer
Error code P0171 on your Toyota SUVs means: System Too Lean Bank 1. This is usually fixable — see the step-by-step guide below.
Affected Models
Applies to all models
4Runner TRD Pro 2024Grand Highlander Limited 2024Highlander XLE 2024Highlander Hybrid Bronze Edition 2023Land Cruiser 1958 Edition 2024RAV4 XLE Premium 2024RAV4 Hybrid SE 2024Sequoia Capstone 20244Runner Limited 20244Runner SR5 20244Runner TRD Off-Road 2024Grand Highlander Platinum 2024Grand Highlander XLE 2024Highlander LE 2024Highlander Limited 2024Highlander Platinum 2024RAV4 Adventure 2024RAV4 LE 2024RAV4 TRD Off-Road 2024RAV4 XLE 2024Sequoia Limited 2024Sequoia Platinum 2024Sequoia SR5 2024Sequoia TRD Pro 2024Venza Limited 2024
Likely Causes
How to Fix It
1
Perform a smoke test on the intake system to locate vacuum leaks
2
Remove and clean the MAF sensor with MAF-specific cleaner
3
Check fuel pressure at the rail and compare to Toyota specifications
4
Inspect fuel injector O-rings and replace if cracked or brittle
5
Check for exhaust leaks near the exhaust manifold
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
MAF sensor
Intake manifold gasket
Vacuum hoses
Fuel injector O-rings
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