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 how the engine's computer is trying to turn off one of the engine's cylinders (number 5) to save fuel. It's like trying to turn off a light, but the switch isn't working right.
The engine control module (ECM) is unable to properly deactivate the intake valve for cylinder 5, affecting the cylinder's performance.
The P349C code indicates that the ECM has detected an issue with the deactivation of the intake valve for cylinder 5. This could be due to a malfunction in the valve control solenoid, a mechanical issue with the valve itself, or an electrical problem in the circuit.
• Check Engine Light is on
• Reduced engine performance
• Increased fuel consumption
• Faulty intake valve control solenoid
• Electrical issue in the valve control circuit
• Mechanical problem with the intake valve
ECM: Engine Control Module
Solenoid: A device that converts electrical energy into mechanical movement
• Scan the vehicle for additional trouble codes.
• Inspect the wiring and connectors for the intake valve control solenoid.
• Test the intake valve control solenoid for proper operation.
• Replace the intake valve control solenoid if faulty.
• Repair or replace damaged wiring or connectors.
• Inspect and repair any mechanical issues with the intake valve.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Chevrolet Silverado
• GMC Sierra
• Cadillac Escalade
• Regular maintenance of the engine
• Ensure timely oil changes
• Inspect electrical connections periodically
Engine Performance
• Avoid heavy acceleration until the issue is resolved.
• Consult a professional mechanic for accurate diagnosis.
Check with the vehicle manufacturer for warranty coverage on engine components.
This code has been more prevalent in vehicles with cylinder deactivation technology, especially in models from the mid-2010s.
Moderate – It should be addressed soon to prevent further engine issues.
Driving with this code may lead to increased emissions. It is advisable to fix the issue to comply with emission standards.
• Engine at operating temperature
• Vehicle in a controlled environment
The intake valve control solenoid for cylinder 5 is typically located on the engine block, near the cylinder head.
Q: Can I drive with a P349C code?
A: While you can drive with this code, it's best to have it fixed soon to avoid further engine issues.
Q: Does this code affect fuel efficiency?
A: Yes, it can lead to increased fuel consumption as the engine may not deactivate the cylinder properly.
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