how to fix P0171 code in Ford Explorer Fifth Generation (2011-2019)

Ford Explorer Fifth Generation (2011-2019)

Error Codes

2-4 hours

Time

medium

Difficulty

medium

Severity

Error Code: P0171

3 min read

553 words

Problem Statement

Learn how to diagnose and fix P0171 engine lean condition in Ford Explorer (2011-2019). Step-by-step guide with diagnostic procedures and repair instructions.

Error Code

P0171

Affected Component

Engine

Estimated Time

2-4 hours

⚠️ Safety Warnings

Important safety information - read before proceeding

•Disconnect the battery before working on electrical systems.
•Relieve fuel pressure prior to disconnecting fuel lines to prevent spray or leaks.

Symptoms

•Check engine light illuminated
•Rough idle or stalling
•Decreased fuel economy
•Engine hesitation or misfire during acceleration
•Increased emissions

Diagnostic Steps

1
Scan for error codes using an OBD-II scanner to confirm the P0171 code.
2
Inspect the air intake system for vacuum leaks or damaged hoses.
3
Check the fuel pressure to ensure it meets specifications.
4
Examine the mass airflow (MAF) sensor for dirt or malfunction.
5
Inspect the fuel injectors for proper operation and clogs.
6
Verify the operation of the oxygen sensors.

Solution

💡 Expert Tip

For complex repairs like this, consider taking photos at each step. This helps if you need to reverse a step or consult with a mechanic. Also, keep all removed parts organized - you may need to reference them during reassembly.

Verification

After completing the repair, verify that the issue has been resolved:

✓Test the affected component to ensure it functions correctly
✓Check for any error codes or warning lights
✓Monitor the vehicle for a few days to ensure the issue does not recur

Prevention Tips

To prevent this issue from occurring again:

•Follow the manufacturer's recommended maintenance schedule
•Address warning signs early before they develop into major issues
•Use quality parts and fluids recommended for your vehicle
•Keep detailed records of all repairs and maintenance

Tools & Equipment Required

•OBD-II scanner
•Vacuum gauge
•Fuel pressure gauge
•Multimeter
•Socket set
•Cleaning supplies

Parts Required

•Vacuum hoses (if damaged)
•MAF sensor cleaner
•Fuel injectors (if faulty)
•Fuel filter (if needed)

Related Faults

Share this solution

Comments

No comments yet

Be the first to share your thoughts

Back to Generation

Diagnostic Steps

1
Scan for error codes using an OBD-II scanner to confirm the P0171 code.
2
Inspect the air intake system for vacuum leaks or damaged hoses.
3
Check the fuel pressure to ensure it meets specifications.
4
Examine the mass airflow (MAF) sensor for dirt or malfunction.
5
Inspect the fuel injectors for proper operation and clogs.
6
Verify the operation of the oxygen sensors.

Solution

1. Preparation

Tools Required: OBD-II scanner, vacuum gauge, fuel pressure gauge, multimeter, socket set, cleaning supplies.
Disconnect the negative battery terminal to prevent electrical shorts.

2. Inspect and Repair Vacuum Leaks

Sub-steps:
- Visually inspect all vacuum hoses connected to the intake manifold for cracks or disconnections.
- Use a vacuum gauge to check for leaks; if pressure is lower than specifications, locate and repair leaks.
- Replace any damaged hoses with OEM parts.

3. Check and Clean the MAF Sensor

Sub-steps:
- Locate the MAF sensor on the air intake duct.
- Disconnect the electrical connector and remove the sensor using a socket set.
- Clean the sensor with MAF cleaner spray; do not touch the sensor element.
- Reinstall the sensor and reconnect the electrical connector.

4. Test Fuel Pressure

Sub-steps:
- Attach the fuel pressure gauge to the fuel rail Schrader valve.
- Turn the ignition to the "ON" position without starting the engine and check the pressure; it should meet manufacturer specifications (generally around 50-60 psi).
- If pressure is low, inspect the fuel pump and filter; replace if necessary.

5. Inspect Fuel Injectors

Sub-steps:
- Remove the fuel rail with injectors attached (ensure fuel pressure is relieved).
- Check for clogged injectors by performing a flow test or using a cleaning kit.
- Replace any faulty injectors with OEM or compatible replacements.

6. Reset the ECM

Sub-steps:
- Reconnect the negative battery terminal.
- Use the OBD-II scanner to clear the P0171 code and any other related codes.
- Start the vehicle and let it idle to ensure the code does not reappear.