why does my Ford Explorer Fifth Generation (2011-2019) check engine light keep coming on

Ford Explorer Fifth Generation (2011-2019)

Error Codes

1-3 hours

Time

medium

Difficulty

medium

Severity

Error Code: P0420

3 min read

545 words

Problem Statement

Learn how to diagnose and fix P0420 check engine light issue in Ford Explorer (2011-2019). Step-by-step guide with diagnostic procedures and repair instructions.

Error Code

P0420

Affected Component

Engine

Estimated Time

1-3 hours

⚠️ Safety Warnings

Important safety information - read before proceeding

•Disconnect the battery before working on electrical components.
•Allow the engine to cool before performing any repairs.

Symptoms

•Check engine light illuminated
•Rough idle when the engine is running
•Decreased fuel efficiency
•Engine stalling or hesitating during acceleration
•Unusual engine noises (knocking or pinging)
•Increased emissions or failed emissions test

Diagnostic Steps

1
Scan for error codes using an OBD-II scanner to identify specific trouble codes.
2
Inspect the gas cap for proper sealing and check for any cracks or damage.
3
Check the engine oil and coolant levels to ensure they are within normal ranges.
4
Visually inspect wiring and connectors related to the engine management system for signs of wear or damage.
5
Test the battery and charging system to ensure proper voltage supply.
6
Evaluate the condition of spark plugs and ignition coils for wear or failure.

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
•Socket set
•Torque wrench
•Spark plug socket

Parts Required

•New gas cap
•Spark plugs
•Oxygen sensor (if applicable)

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 identify specific trouble codes.
2
Inspect the gas cap for proper sealing and check for any cracks or damage.
3
Check the engine oil and coolant levels to ensure they are within normal ranges.
4
Visually inspect wiring and connectors related to the engine management system for signs of wear or damage.
5
Test the battery and charging system to ensure proper voltage supply.
6
Evaluate the condition of spark plugs and ignition coils for wear or failure.

Solution

1. Preparation

Gather necessary tools and parts.
Ensure the vehicle is parked on a level surface and the engine is cool.
Disconnect the battery to prevent electrical shorts during work.

2. Address Check Engine Codes

Use the OBD-II scanner to retrieve trouble codes.
Look up the codes to determine the specific issues (e.g., P0420 for catalytic converter efficiency).
Based on the codes, prioritize repairs or component replacements.

3. Inspect and Replace Components

For Common Issues:

Gas Cap Replacement:
- Remove the gas cap and inspect for damage.
- Replace with a new gas cap if cracked or not sealing correctly.
Spark Plug Replacement:
- Remove the ignition coils using a socket set.
- Unscrew the old spark plugs with a spark plug socket and replace them with new ones.
- Torque new spark plugs to manufacturer specifications (typically 13-15 lb-ft).
Oxygen Sensor Replacement:
- Locate the faulty oxygen sensor as per the error codes.
- Disconnect the electrical connector and unscrew the old sensor.
- Install the new oxygen sensor, ensuring it's properly torqued (usually 30 lb-ft).

4. Reconnect and Test

Reconnect the battery.
Clear the check engine codes using the OBD-II scanner.
Test drive the vehicle to monitor if the check engine light reappears.