Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer is having trouble controlling the first cylinder in the engine. It's like trying to turn off a light switch, but the light doesn't go off when it should.
The P3402 code indicates a problem with the deactivation or control of the intake valve for cylinder 1. This is part of the engine's cylinder deactivation system, which helps save fuel by turning off some cylinders when full power isn't needed.
The P3402 code is triggered when the Engine Control Module (ECM) detects an issue with the intake valve control circuit for cylinder 1. This can involve the solenoid responsible for deactivating the cylinder, the wiring, or the ECM itself. The system is designed to deactivate certain cylinders to improve fuel efficiency under light load conditions.
• Check Engine Light illuminated
• Reduced engine performance
• Increased fuel consumption
• Faulty cylinder deactivation solenoid
• Wiring issues in the intake valve control circuit
• Malfunctioning Engine Control Module (ECM)
ECM: Engine Control Module, the computer that controls engine functions.
Solenoid: An electromechanical device that controls a valve or switch.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for cylinder 1's intake valve control circuit.
• Test the cylinder deactivation solenoid for proper operation.
• Replace the faulty cylinder deactivation solenoid.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Chevrolet Silverado
• GMC Sierra
• Cadillac Escalade
• Regular maintenance and inspection of the engine components.
• Ensure proper oil levels and quality.
• Address any warning lights promptly.
Engine Performance
• Have the vehicle inspected by a professional mechanic.
• Avoid heavy acceleration until the issue is resolved.
Check with the vehicle manufacturer for warranty coverage on engine components.
Cylinder deactivation systems have been used in vehicles to improve fuel efficiency, and issues with these systems have been documented since their introduction.
Moderate – While the vehicle may still be drivable, ignoring the issue can lead to decreased fuel efficiency and potential engine damage.
Driving with a malfunctioning engine can lead to increased emissions and may not comply with local environmental regulations.
• Engine at operating temperature
• Vehicle driven under light load conditions
The cylinder deactivation solenoid for cylinder 1 is typically located near the top of the engine, close to the intake manifold.
Q: Can I drive my car with a P3402 code?
A: It's possible to drive with this code, but it's not recommended as it can lead to increased fuel consumption and potential engine damage.
Q: What happens if I ignore the P3402 code?
A: Ignoring this code can result in decreased fuel efficiency and may cause further damage to the engine over time.
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