p0171
Moderate
Ford · SUVs
System Too Lean Bank 1
Quick Answer
Error code P0171 on your Ford SUVs means: System Too Lean Bank 1. This is usually fixable — see the step-by-step guide below.
Affected Models
Applies to all models
BRNCOBRNCSEDGEESCPEEXPDNEXPLREXPLRHBronco Badlands 2024Bronco Base 2024Bronco Big Bend 2024Bronco Raptor 2024Bronco Sport Badlands 2024Bronco Sport Base 2024Bronco Sport Big Bend 2024Bronco Wildtrak 2024Escape Active 2024Escape Platinum 2024Escape ST-Line 2024Expedition King Ranch 2024Expedition Limited 2024Expedition Platinum 2024Expedition XLT 2024Explorer Base 2024Explorer Limited 2024Explorer Platinum 2024Explorer ST 2024Explorer XLT 2024MACHE
Likely Causes
How to Fix It
1
Inspect intake manifold gaskets and vacuum hoses for leaks
2
Clean or replace the MAF sensor
3
Test fuel pressure at the fuel rail with a pressure gauge
4
Check fuel injectors for proper spray pattern and flow
5
Inspect exhaust manifold for leaks on bank 1
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 or MAF cleaner
Vacuum hoses
Fuel filter
Intake manifold gasket
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