How to fix P0171 and P0174 System Running Lean Bank 1 and Bank 2 If you’re experiencing P0171 and P0174 system running lean, check for “fuel trims” in your bank 1 and bank 2. This video will show you how to diagnose and fix the issue using a simple scan tool. In this video, we’ll show you how to diagnose and fix the issue using a simple scan tool.
If you’re experiencing P0171 and P0174 system running lean, make sure to check for “fuel trims” in your bank 1 and bank 2. This will help to fix the issue and get your engine running smoothly again! if your car is setting lean obd code at idle it is most likely a vacuum leak. if it is running lean off idle you will need to look at other things like the mass air flow sensor for your problem