Effectiveness Of The Vvt-I System Operation; Advance; Retard; Hold - Toyota 1NZ-FE User Manual

EG-44
Operation

1) Advance

When the camshaft timing oil control valve is operated as illustrated below by the advance signals from
the ECM, the resultant oil pressure is applied to the timing advance side vane chamber to rotate the
camshaft in the timing advance direction.
Vane
Rotation Direction

2) Retard

When the camshaft timing oil control valve is operated as illustrated below by the retard signals from
the ECM, the resultant oil pressure is applied to the timing retard side vane chamber to rotate the camshaft
in the timing retard direction.
Vane
Rotation Direction

3) Hold

After reaching the target timing, the valve timing is held by keeping the camshaft timing oil control valve
in the neutral position unless the traveling state changes.
This adjusts the valve timing at the desired target position and prevents the engine oil from running out
when it is unnecessary.
ENGINE - 1NZ-FE ENGINE
IN Drain
Oil Pressure
ECM
Drain IN
Oil Pressure
ECM
198EG35
198EG36