P0171 - System Too Lean Bank 1
P0171 Causes
P0171 Notes
If the P0171 is combined with the P0174 code, it's very likely that the problem is caused by an intake leak. If there are no intake leaks, the next step is to replace the air filter and clean the air flow meter. If the problem persists the front oxygen (O2) sensor may need to be replaced.User Submitted Video
First diagnose P0171 code
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Check the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded terminals.
Cost of diagnosing the P0171 code
Labor: 1.0
The cost of diagnosing the P0171 code is 1.0 hour of labor. The auto repair labor rates vary widely across the country, and even within the same city. Most auto repairs shops charge between $75 and $150 per hour.P0171 Symptoms
P0171 More Information
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P0171 Description
With the Air/Fuel Mixture Ratio Self-Learning Control, the actual mixture ratio can be brought closely to the theoretical mixture ratio based on the mixture ratio feedback signal from the heated oxygen sensors 1. The Engine Control Module (ECM) calculates the necessary compensation to correct the offset between the actual and the theoretical ratios.In case the amount of the compensation value is extremely large (The actual mixture ratio is too lean.), the ECM judges the condition as the fuel injection system malfunction and light up the Malfunction Indicator Light (MIL) (2 trip detection logic).
P0171 Information for specific makes
- P0171 ACURA Fuel Injection System Too Lean Bank 1
- P0171 AUDI System Too Lean Bank 1
- P0171 BMW Mixture Control System Too Lean
- P0171 BUICK Fuel Trim System Lean Bank 1
- P0171 CADILLAC Fuel Trim System Lean Bank 1 Show more makes....