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Variable Valve Timing with Intelligence Explained

Variable Valve Timing with Intelligence Explained


(VVT-i) which stands for Variable Valve Timing with Intelligence is a technology developed by Toyota and available on all Toyota vehicles to help optimize the balance of power, economy, and emissions control.


It helps the engine breathe more efficiently by adjusting the timing of the intake valve opening and closing to suit specific operating conditions.


  • Without VVT-i, the valves would always open and close with the same timing, regardless of speed or operating conditions.
  • Without VVT-i, the engine would not be operating at optimum efficiency.


VVT-i helps overcome those inefficiencies. In effect, it helps match the engine’s performance to the existing driving conditions by automatically varying the valve timing to suit engine speed and load.



Toyota VVT-i  Benefits


VVT-i helps the engine deliver low-speed torque when it’s needed without compromising high-speed horsepower. It also lets the engine breathe efficiently when the engine is idling or operating with light accelerator pressure as during around-town driving and low-speed cruising.


It even allows more complete filling of the intake manifold with the air & fuel mixture when the engine is running at high speed to maximize power output.



That additional level of control promotes more complete combustion of the air-fuel mixture which reduces the emission of air pollutants.


Dual VVT-i adds the same type of variable valve timing control to the engine's exhaust valves, further enhancing both performance and fuel economy and reducing exhaust emissions.


Other VVT-i  Benefits Include:

  • Improved start ability
  • Stabilized idle speed
  • Improved torque in a low-to-medium speed range
  • Better fuel economy at low temperatures


In short, VVT-i is a win-win technology that benefits performance, fuel economy, and emissions control, all at the same time.

Categories: Service, Technology

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