How does variable valve timing in a camshaft work?
So, With Dual (VVT-i) – Variable Valve Timing, the same thing happens, the difference this time is the exhaust valves are activated. Now, The camshaft has two profiles each for both intake and exhaust. Dual (VVTi) also minimises the start/stop compression pressures by adjusting…
How is the camshaft different from the intake and exhaust valves?
Because the camshaft is further away from the intake and exhaust valves a different configuration of the rocker arm and lifter is used. The lifter now rides along the camshaft with the camshaft lobe cut at a slight angle at the top of the lobe which spins the lifter slightly to help cut down on wear.
Where is the camshaft actuator control valve located?
An electronically controlled camshaft actuator valve is positioned at the front or rear of the camshaft or in the engine block to divert pressurized oil to one side of the actuator or the other. The actuator control valve receives signals from the computer to move the cam one way or the other.
What are the symptoms of a bad variable valve timing?
Symptoms of a Bad or Failing Variable Valve Timing (VVT) Solenoid. Cost of Replacing a Bad or Failing Variable Valve Timing (VVT) Solenoid. Common signs of a faulty VVT solenoid include the Check Engine Light coming on, dirty engine oil, rough engine idle, and decreased fuel economy.
What does variable valve timing ( VVT ) do?
Variable Valve Timing (VVT) is used to vary engine performance and enhancements. On dual cam systems, the PCM controls the amount of variance on both cams separately. There are two actuators in the system; one for the exhaust cam and one for the intake cam.
Because the camshaft is further away from the intake and exhaust valves a different configuration of the rocker arm and lifter is used. The lifter now rides along the camshaft with the camshaft lobe cut at a slight angle at the top of the lobe which spins the lifter slightly to help cut down on wear.
An electronically controlled camshaft actuator valve is positioned at the front or rear of the camshaft or in the engine block to divert pressurized oil to one side of the actuator or the other. The actuator control valve receives signals from the computer to move the cam one way or the other.
When did Nissan start using variable valve timing?
In 1987 Nissan debuted their electronic variable valve timing technology called NVCS in their DOHC VG20DET and VG30DE engines. In 1989, Honda released the VTEC system. While the earlier Nissan NVCS alters the phasing of the camshaft, VTEC switches to a separate cam profile at high engine speeds to improve peak power.