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 there's a problem with a special part of the car that helps it run smoothly. It's like when a toy's battery is low, and it can't work properly. The car has a backup mode to keep it running, but it won't be as good as normal.
The P1003 code indicates that the Variable Valve Lift (VVL) system's circuit is open. This system adjusts how the engine's valves open and close to improve performance and efficiency.
The P1003 code is triggered when the Engine Control Module (ECM) detects an open circuit in the Variable Valve Lift (VVL) system. The VVL system is responsible for adjusting the valve lift for optimal engine performance. An open circuit means that there is a break or disconnection in the electrical path that controls this system.
• Reduced engine performance
• Check Engine Light illuminated
• Poor fuel economy
• Faulty VVL solenoid
• Damaged wiring or connectors
• Blown fuse related to the VVL circuit
VVL: Variable Valve Lift
ECM: Engine Control Module
• Use an OBD-II scanner to confirm the code.
• Inspect the VVL solenoid and wiring for damage.
• Check for blown fuses in the VVL circuit.
• Replace the faulty VVL solenoid.
• Repair or replace damaged wiring or connectors.
• Replace any blown fuses.
• OBD-II scanner
• Multimeter
• Socket set
$150 - $400
Moderate
• Nissan Altima
• Infiniti G35
• Nissan Maxima
• Regularly inspect and maintain engine components.
• Ensure electrical connections are secure.
• Follow the vehicle's recommended maintenance schedule.
Engine Performance
• Avoid driving aggressively until the issue is resolved.
• Have the car inspected by a professional mechanic.
• Monitor fuel economy for any changes.
Check with your vehicle manufacturer or warranty provider to see if this issue is covered under warranty.
The P1003 code has been associated with vehicles that have advanced valve timing systems. It is more common in models with higher mileage.
Moderate – While the car can still operate, performance and fuel efficiency are affected. Prompt attention is recommended.
Driving with a malfunctioning VVL system may lead to increased emissions, which could be subject to legal penalties in some areas.
• Engine at operating temperature
• Vehicle in idle or low-speed conditions
The VVL solenoid is typically located on the cylinder head, near the camshaft.
Q: Can I drive with a P1003 code?
A: While you can drive with this code, it's best to get it fixed soon to avoid further issues.
Q: What happens if I ignore the P1003 code?
A: Ignoring the code can lead to reduced engine performance and efficiency, and possibly more severe engine damage over time.
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