Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer is having trouble controlling the exhaust valve for cylinder 7 because it is getting too much electrical power.
This code indicates that the exhaust valve control circuit for cylinder 7 is experiencing a high voltage condition.
The P3456 code is triggered when the Engine Control Module (ECM) detects a high voltage condition in the exhaust valve control circuit for cylinder 7. This can affect the performance of the engine and lead to increased emissions.
• Check Engine Light illuminated
• Poor engine performance
• Increased fuel consumption
• Faulty exhaust valve control solenoid
• Wiring issues such as short to voltage
• Faulty ECM
ECM: Engine Control Module, the computer that controls engine functions.
Solenoid: A device that converts electrical energy into mechanical movement.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for cylinder 7 exhaust valve control circuit.
• Test the exhaust valve control solenoid for proper operation.
• Replace faulty exhaust valve control solenoid.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Honda Accord
• Acura TL
• Chevrolet Silverado
• Regular maintenance and inspection of wiring.
• Ensure proper lubrication of engine components.
• Use high-quality fuel to prevent deposits.
Engine Performance
• Avoid driving with the Check Engine Light on for extended periods.
• Have the vehicle inspected by a professional mechanic.
• Keep up with regular vehicle maintenance.
Check with your vehicle manufacturer for warranty coverage on engine components.
This code is commonly associated with vehicles that have variable valve timing systems.
Moderate – Should be addressed soon to prevent further engine issues.
Driving with a malfunctioning engine may lead to increased emissions and could be illegal in some areas.
• Engine at normal operating temperature
• Vehicle in a safe, stationary position
The exhaust valve control solenoid is typically located on or near the engine cylinder head.
Q: Can I drive my car with a P3456 code?
A: It's not recommended to drive for extended periods with this code, as it can lead to engine damage.
Q: How can I reset the Check Engine Light?
A: You can reset it with an OBD-II scanner after fixing the issue, but it will come back if the problem persists.
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