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 can't remember the positions of certain engine parts that help it run smoothly.
The Variable Valve Lift (VVL) system has a self-learning function that stores positions for optimal performance. This code indicates that no positions are stored for Bank 1.
P1025 is triggered when the engine control module (ECM) detects that the VVL system's self-learning function has not stored any positions for the camshaft or valve timing on Bank 1. This can affect the engine's efficiency and performance.
• Check Engine Light is on
• Reduced engine performance
• Poor fuel economy
• Faulty VVL actuator
• Wiring issues or poor connections
• Faulty ECM
VVL: Variable Valve Lift
ECM: Engine Control Module
• Check for any other related codes and address them first.
• Inspect the VVL actuator and related wiring for damage or disconnection.
• Test the ECM for faults or malfunctions.
• Repair or replace the VVL actuator if faulty.
• Fix any wiring issues or poor connections.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $800
Moderate
• Nissan Altima
• Nissan Maxima
• Infiniti G35
• Regular maintenance of the VVL system
• Ensure wiring and connectors are in good condition
• Keep the ECM software updated
Engine Performance
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if unsure.
• Regularly maintain the vehicle to prevent such issues.
Check with the vehicle manufacturer for warranty coverage related to the VVL system and ECM.
This code is often associated with Nissan and Infiniti vehicles equipped with VVL technology, highlighting the importance of proper VVL system maintenance.
Moderate – While not immediately critical, it can lead to reduced performance and efficiency if not addressed.
Driving with a malfunctioning VVL system can lead to increased emissions and potential engine damage.
• Engine at normal operating temperature
• Vehicle at idle or low speed
The VVL actuator is typically located on the cylinder head of the engine.
Q: What is VVL?
A: VVL stands for Variable Valve Lift, a system that adjusts the lift of the engine's valves for better performance and efficiency.
Q: Can I drive with a P1025 code?
A: It's possible to drive, but it's not recommended as it can lead to reduced performance and potential engine damage.
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