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 the system that turns off one of the engine's cylinders to save fuel. It's like one of the engine's helpers isn't doing its job right.
The P3490 code indicates an issue with the deactivation of cylinder 12, specifically related to the intake valve control circuit. This system is designed to improve fuel efficiency by deactivating certain cylinders under light load conditions.
The P3490 code is triggered when the Powertrain Control Module (PCM) detects a performance issue in the intake valve control circuit for cylinder 12. This could be due to a malfunction in the cylinder deactivation solenoid, wiring issues, or a problem with the PCM itself.
• Check Engine Light illuminated
• Reduced engine performance
• Poor fuel economy
• Faulty cylinder deactivation solenoid
• Wiring or connector issues in the circuit
• Faulty Powertrain Control Module (PCM)
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors related to cylinder 12 deactivation.
• Test the cylinder deactivation solenoid for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the faulty cylinder deactivation solenoid.
• Reprogram or replace the PCM if necessary.
• OBD-II scanner
• Multimeter
• Socket set
$200 - $600
Moderate
• Chevrolet Silverado
• GMC Sierra
• Cadillac Escalade
• Regular maintenance and inspection of engine components
• Timely replacement of faulty solenoids
• Ensure proper electrical connections
Engine Performance
• Have the vehicle inspected by a professional if the Check Engine Light is on.
• Avoid heavy driving until the issue is resolved to prevent further damage.
Check with the vehicle manufacturer for warranty coverage on engine components.
This code has been associated with vehicles that use cylinder deactivation technology to improve fuel efficiency.
Moderate – Addressing this issue promptly can prevent further engine damage and maintain fuel efficiency.
Driving with a malfunctioning engine can lead to safety issues and may not comply with emissions regulations.
• Engine at operating temperature
• Vehicle running under light load conditions
The cylinder deactivation solenoid for cylinder 12 is typically located on the engine block, near the intake valve.
Q: Can I drive with a P3490 code?
A: It's possible to drive with this code, but it's not recommended as it can lead to reduced engine performance and efficiency.
Q: Will the P3490 code clear itself?
A: The code may clear if the issue is resolved, but it's best to use a scanner to clear it and confirm the fix.
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