Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with a part of your car that helps control the airflow to the engine. It's like a door that opens and closes to let air in, but it might be stuck or not working right.
The P14C4 code is triggered when the vehicle's computer detects a mechanical issue with the upper air shutter, which is responsible for regulating airflow to the engine for optimal performance and efficiency.
The upper air shutter is part of the vehicle's active grille shutter system, which opens and closes to control airflow to the engine compartment. This system helps improve aerodynamics and fuel efficiency. A mechanical issue could involve the shutter being stuck, not opening or closing properly, or having a motor or linkage failure.
• Check engine light on
• Reduced fuel efficiency
• Unusual noises from the front of the vehicle
• Stuck or jammed air shutter
• Faulty air shutter motor
• Damaged linkage or actuator
Air Shutter: A component that controls airflow to the engine.
Actuator: A device that moves or controls a mechanism or system.
• Perform a visual inspection of the air shutter for obstructions.
• Check the operation of the air shutter motor.
• Test the electrical connections and wiring to the shutter motor.
• Clean and remove any obstructions from the air shutter.
• Replace the air shutter motor if faulty.
• Repair or replace damaged linkages or actuators.
• OBD-II scanner
• Multimeter
• Socket set
$150 - $400
Moderate
• Chevrolet Silverado
• GMC Sierra
• Ford F-150
• Regularly inspect the grille area for debris.
• Ensure the air shutter system is clean and free of obstructions.
• Perform routine maintenance checks on the air shutter system.
Mechanical Issue
• Avoid driving through deep water or muddy areas that might clog the shutter.
• Have the air shutter system checked during regular vehicle maintenance.
Check with your vehicle manufacturer as some air shutter components may be covered under warranty.
This code has become more common with the introduction of active grille shutter systems in modern vehicles to improve fuel efficiency.
Moderate – It should be addressed soon to maintain fuel efficiency and prevent further issues.
Ignoring this issue could lead to decreased vehicle performance and efficiency, potentially affecting emissions compliance.
• Vehicle at operating temperature
• Grille area free from obstructions
The upper air shutter is typically located behind the vehicle's front grille.
Q: What happens if I ignore this code?
A: Ignoring this code can lead to reduced fuel efficiency and potential damage to the air shutter system.
Q: Can I drive with this code?
A: You can drive with this code, but it's best to have it checked soon to avoid further issues.
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Specialty · Compression tester
Useful when misfire, mechanical condition, or low-cylinder-pressure problems are suspected.
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