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

Ford Explorer Fifth Generation (2011-2019)

Error Codes

2-4 hours

Time

medium

Difficulty

high

Severity

Error Code: P0171

4 min read

628 words

⚠️ Safety Warning

This issue requires immediate attention. If you are not experienced with automotive repairs, consult a professional mechanic. Working on critical systems can be dangerous.

Problem Statement

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

Error Code

P0171

Affected Component

Engine

Estimated Time

2-4 hours

⚠️ Safety Warnings

Important safety information - read before proceeding

•Disconnect battery before working on electrical systems.
•Allow engine to cool before working on intake components.

Symptoms

•Check engine light illuminated
•Rough idle or stalling
•Poor acceleration or loss of power
•Decreased fuel economy
•Engine misfires
•Unusual fuel smells

Diagnostic Steps

1
Scan the vehicle's onboard diagnostics using an OBD-II scanner to confirm the P0171 code and check for any additional codes.
2
Inspect the air intake system for vacuum leaks or damaged hoses.
3
Check the mass air flow (MAF) sensor for proper operation and cleanliness.
4
Examine fuel system components, including fuel pressure and fuel filter condition.
5
Inspect the throttle body for carbon buildup or obstruction.
6
Test the oxygen sensor's performance and functionality.

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
•Throttle body cleaner
•MAF sensor cleaner
•Socket set
•Torque wrench

Parts Required

•Mass air flow sensor (if cleaning does not resolve issue)
•Oxygen sensor (if testing shows it is faulty)
•Fuel filter (if clogged)

Related Faults

Share this solution

Comments

No comments yet

Be the first to share your thoughts

Back to Generation

Diagnostic Steps

1
Scan the vehicle's onboard diagnostics using an OBD-II scanner to confirm the P0171 code and check for any additional codes.
2
Inspect the air intake system for vacuum leaks or damaged hoses.
3
Check the mass air flow (MAF) sensor for proper operation and cleanliness.
4
Examine fuel system components, including fuel pressure and fuel filter condition.
5
Inspect the throttle body for carbon buildup or obstruction.
6
Test the oxygen sensor's performance and functionality.

Solution

1. Preparation

Gather tools and parts required for the repair.
Disconnect the negative battery terminal to ensure safety during the procedure.

2. Inspect and Repair Vacuum Leaks

Sub-steps:
1. Visually inspect all vacuum hoses connected to the intake manifold for cracks or disconnections.
2. Use a smoke machine or carburetor cleaner to identify any leaks by applying it around suspected areas and observing for changes in idle speed.
3. Replace any damaged hoses or repair connections as necessary.

3. Clean or Replace the MAF Sensor

Sub-steps:
1. Locate the MAF sensor in the air intake duct.
2. Disconnect the electrical connector from the sensor.
3. Remove the MAF sensor from the duct using a Torx or socket wrench.
4. Clean the sensor element with MAF sensor cleaner and allow it to dry, or replace it if damaged.
5. Reinstall the sensor and reconnect the electrical connector.

4. Test and Adjust Fuel Pressure

Sub-steps:
1. Locate the fuel rail and connect a fuel pressure gauge to the test port.
2. Turn the ignition key to the "on" position without starting the engine to build pressure.
3. Check the pressure reading against the manufacturer specifications (typically 30-50 psi).
4. If pressure is low, check the fuel pump operation and replace the fuel filter if clogged.

5. Clean the Throttle Body

Sub-steps:
1. Remove the air intake duct connected to the throttle body.
2. Use throttle body cleaner and a soft brush to clean the throttle plate and surrounding areas.
3. Reassemble the air intake duct securely.

6. Replace Oxygen Sensor (if necessary)

Sub-steps:
1. Locate the bank 1 oxygen sensor (typically before the catalytic converter).
2. Disconnect the electrical connector.
3. Use an oxygen sensor socket to remove the sensor.
4. Install the new sensor and reconnect the electrical connector.