Effectiveness Of The Vvt-I System Construction; Vvt-I Controller; Camshaft Timing Oil Control Valve - Toyota 1NZ-FE User Manual

Construction

1) VVT-i Controller

This controller consists of the housing driven from the timing chain and the vane coupled with the intake
camshaft.
The oil pressure sent from the advance or retard side path at the intake camshaft causes rotation in the
VVT-i controller vane circumferential direction to vary the intake valve timing continuously.
When the engine is stopped, the intake camshaft will be in the most retarded state to ensure startability.
When hydraulic pressure is not applied to the VVT-i controller immediately after the engine has been
started, the lock pin locks the movement of the VVT-i controller to prevent a knocking noise.

2) Camshaft Timing Oil Control Valve

This camshaft timing oil control valve controls the spool valve position in accordance with the duty-cycle
control from the ECM. This allows hydraulic pressure to be applied to the VVT-i controller advance or
retard side. When the engine is stopped, the camshaft timing oil control valve is in the most retarded state.
to VVT-i Controller
(Advance Side)
Sleeve
Spring
ENGINE - 1NZ-FE ENGINE
Housing
Lock Pin
At a Stop In Operation
Lock Pin
to VVT-i Controller
(Retard Side)
Drain Drain
Oil Pressure
Intake Camshaft
Vane (Fixed on Intake Camshaft)
Oil Pressure
Plunger
Coil
Spool Valve
EG-43
169EG36
221EG17