Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means the car's computer has detected a problem with the system that turns off cylinder 1 in the engine to save fuel. It's like a switch that isn't working right.
The P3401 code is triggered when the Powertrain Control Module (PCM) detects an issue with the circuit responsible for deactivating cylinder 1's intake valve.
In vehicles equipped with cylinder deactivation technology, the PCM controls the intake and exhaust valves to deactivate certain cylinders under light load conditions to improve fuel efficiency. Code P3401 indicates that the PCM has found an open or malfunction in the control circuit for the intake valve of cylinder 1.
• Check Engine Light is on
• Reduced engine performance
• Poor fuel economy
• Faulty intake valve control solenoid
• Open or shorted wiring in the intake valve control circuit
• Faulty PCM
PCM: Powertrain Control Module, the computer that controls the engine and transmission.
Solenoid: An electromechanical device that controls the flow of fluid or air.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for the intake valve control solenoid.
• Test the intake valve control solenoid for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace faulty intake valve control solenoid.
• Reprogram or replace the PCM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Chevrolet Silverado
• GMC Sierra
• Cadillac Escalade
• Regular maintenance and inspection of the engine's electrical components.
• Ensure proper oil changes to maintain engine health.
• Avoid overloading the vehicle to prevent excessive engine strain.
Engine Performance
• Have the vehicle inspected by a professional mechanic.
• Avoid heavy acceleration until the issue is resolved.
Check with your vehicle manufacturer, as some powertrain warranties may cover this issue.
This code is common in vehicles with cylinder deactivation systems, particularly in GM models.
Moderate – While the vehicle may still be drivable, it's important to address the issue to avoid further damage and maintain fuel efficiency.
Driving with a malfunctioning cylinder deactivation system may lead to increased emissions and fuel consumption.
• Engine at operating temperature
• Vehicle at idle or light load
The intake valve control solenoid for cylinder 1 is typically located on or near the engine cylinder head.
Q: Can I drive with a P3401 code?
A: You can drive, but it's not recommended for long distances as it may reduce fuel efficiency and potentially cause more damage.
Q: Will fixing this code improve my fuel economy?
A: Yes, resolving the issue will help restore the intended fuel-saving benefits of the cylinder deactivation system.
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