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Home/Cars/Ford/F-150/12th Generation (2009-2014)/how to troubleshoot P0303 code on Ford F-150 12th Generation (2009-2014)

how to troubleshoot P0303 code on Ford F-150 12th Generation (2009-2014)

Ford F-150 12th Generation (2009-2014)

Error Codes
Severity: highDifficulty: mediumError Code: P03032-4 hours
3 min read
587 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 P0303 cylinder 3 misfire in Ford F-150 12th Generation. Step-by-step guide with diagnostic and repair instructions.

Error Code
P0303
Affected Component
Engine
Estimated Time
2-4 hours

Safety Warnings

  • ⚠Disconnect the battery before working on electrical systems.
  • ⚠Allow the engine to cool before opening any components to avoid burns.

Symptoms

  • •Check engine light illuminated
  • •Rough idle or engine shaking
  • •Decreased fuel efficiency
  • •Loss of power during acceleration
  • •Engine stalling or hesitation
  • •Increased exhaust emissions

Diagnostic Steps

  1. 1Scan the vehicle's onboard computer using an OBD-II scanner to confirm the P0303 code and check for any related codes.
  2. 2Inspect the ignition coil for cylinder 3 for damage or wear, ensuring it is securely connected.
  3. 3Examine the spark plug for cylinder 3, looking for signs of wear, fouling, or improper gap.
  4. 4Perform a compression test on cylinder 3 to check for mechanical issues such as low compression or leaks.
  5. 5Use a multimeter to test the resistance of the ignition coil and ensure it meets manufacturer specifications.
  6. 6Inspect the fuel injector for cylinder 3 for clogs or malfunctions, ensuring proper fuel delivery.

Solution

Solution

1. Preparation

  • Gather all necessary tools and parts.
  • Disconnect the negative battery terminal to prevent electrical shock.
  • Allow the engine to cool before beginning work.

2. Replace Spark Plug

  • Remove the spark plug wire or ignition coil from cylinder 3.
  • Use a spark plug socket and ratchet to remove the spark plug from cylinder 3.
  • Inspect the old spark plug; if it is damaged or fouled, replace it with a new one, ensuring the gap is set to manufacturer specifications (typically around 0.054 inches for F-150).
  • Reinstall the spark plug and reconnect the ignition coil or wire.

3. Inspect and Replace Ignition Coil

  • If the spark plug replacement does not resolve the issue, remove the ignition coil from cylinder 3.
  • Inspect the ignition coil for cracks or signs of damage; if necessary, replace it with a new coil.
  • Reinstall the ignition coil, ensuring all connections are secure.

4. Test Fuel Injector

  • If misfire persists, test the fuel injector for cylinder 3 by using a noid light or multimeter to check for proper operation.
  • If the injector is malfunctioning, remove and replace it with a new unit.
  • Reconnect all electrical connectors securely.

5. Recheck and Clear Codes

  • Reconnect the negative battery terminal.
  • Start the engine and allow it to idle for a few minutes.
  • Use the OBD-II scanner to clear the P0303 code and monitor for any reoccurrence.

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
  • •Spark plug socket
  • •Ratchet and extensions
  • •Multimeter
  • •Noid light (for fuel injector testing)
  • •Torque wrench

Parts Required

  • •Spark plug for cylinder 3
  • •Ignition coil for cylinder 3 (if needed)
  • •Fuel injector for cylinder 3 (if needed)

Additional Information

Error Code
P0303
Affected Component
Engine
Estimated Time
2-4 hours
Difficulty
medium
Severity
high
Tools Required
6 items
Parts Required
3 items

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