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P0171 Chevrolet Code - Fuel Trim System Lean Bank 1

- Code Popularity: 573,257 Views
- Repair Importance Level: 3/3
- Repair Difficulty Level: 3/3
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By AutoCodes.com - Updated Aug 21, 2022
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|Code P0171 Chevrolet Possible Causes

  • Dirty or Restricted Air Filter
  • Dirty or Faulty Mass Air Flow (MAF) Sensor
  • Intake Air Leaks
  • Exhaust Gas Leaks
  • Fuel Contamination
  • Faulty or Clogged Fuel Injectors
  • Faulty Front Heated Oxygen Sensor
  • Ignition Misfiring
  • Low Fuel Pressure
  • Positive Crankcase Ventilation (PCV) Hose Leaks
  • Engine Control Temperature (ECT) inaccurate readings

|How do I Fix the Code P0171 Chevrolet?

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 connector's pins.

Does your Chevrolet have Safety Recalls? → Check here

|Code P0171 Chevrolet Tech Notes

The P0171 code means that more air than gasoline is detected in the exhaust gases exiting the combustion chamber. If the P0171 is set in along with the P0174 code, it is highly 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 Mass Air Flow (MAF) Sensor. If the problem persists the MAF or Front Heated Oxygen (O2) Sensor will need to be replaced.

Click Here to Learn What is Bank 1 and Bank 2

There are Factory Service Bulletins for the following Chevrolet models:

2000-2013 Chevrolet All Models:
2000-2013 Chevrolet Factory Service Bulletin OBDII Code P0171

2005-2006 Chevrolet Impala
2005-2006 Chevrolet Monte Carlo
2005-2006 Chevrolet TrailBlazer Models
2007 Chevrolet Avalanche
2007 Chevrolet Suburban
2007 Chevrolet Tahoe
Chevrolet Factory Service Bulletin OBDII Code P0171


2006 Trailblazer P0171








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|What is the Cost to Diagnose the Code P0171 Chevrolet?

Labor: 1.0

The cost of diagnosing the P0171 Chevrolet code is 1.0 hour of labor. The auto repair labor rates vary by location, your vehicle's make and model, and even your engine type. Most auto repairs shops charge between $75 and $150 per hour.

|What are Code P0171 Chevrolet Possible Symptoms?

  • Engine Light ON (or Service Engine Soon Warning Light)
  • Excessive Fuel Consumption

|Code P0171 Chevrolet Description

The Engine Control Module (ECM) controls a Closed Loop air/fuel metering system to provide the best possible combination of drivability, fuel economy, and emission control. The ECM monitors the Heated Oxygen Sensor (HO2S) signal voltage and adjusts the fuel delivery based on the signal voltage while in Closed Loop. A change made to the fuel delivery changes the long and short-term fuel trim values. The short-term fuel trim values change rapidly in response to the HO2S signal voltages. These changes fine-tune the engine fueling. The long-term fuel trim values change in response to trends in the short-term fuel trim. The long-term fuel trim makes coarse adjustments to fueling to re-center and restore control to short-term fuel trim. The ideal fuel trim values are around 0 %. A positive fuel trim value indicates that the ECM is adding fuel to compensate for a lean condition. A negative fuel trim value indicates that the ECM is reducing the amount of fuel to compensate for a rich condition. The Diagnostic Trouble Code (DTC) will be set when the average long-term fuel trim weighted average value is greater or less than a calibrated value.

OBDII Code P0171 Chevrolet - Fuel Trim System Lean Bank 1 - AutoCodes.com
P0171 Chevrolet Code - Fuel Trim System Lean Bank 1

|Need More Information on the P0171 Chevrolet Code?

Need more information on how to fix the P0171 Chevrolet code? Get Access to Factory Service Manuals

|Need Help with the P0171 Chevrolet Code?

Get the P0171 Chevrolet code diagnosed by a professional: Find a repair shop in your area

|Code P0171 Chevrolet comments

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