Timing Retarding; Targeted Timing Varying Operation - Suzuki Liana RH418 Supplementary Service Manual

1D-4 Engine Mechanical:

Timing retarding

When the duty ratio of the signal output from the ECM is
light, the spool valve of the oil control valve moves to the
right (head for the coil). By this spool valve movement,
the pressurized oil is led into the chambers for timing
retarding and the oil in the chambers for timing
advancing is drained. This operations actuate the rotor
and result in the retarded timing of the intake valve.

Targeted timing varying operation

DRIVING CONDITION
Engine running at idle
speed
Average engine load
range
Light engine load range To the retarded side
Low or average engine
speed range with heavy
engine load
High engine speed
range with heavy engine
load
Low engine coolant
temperature
At engine starting and
stopping
VALVE TIMING
Most retarded To shorten the valve opening overlap in
order to prevent the exhaust gas counter
flow to intake manifold.
To the advanced side To lengthen the valve opening overlap in
order to enhance the internal exhaust gas
recirculation and reduce the pumping loss.
To shorten the valve opening overlap in
order to prevent the exhaust gas counter
flow to intake manifold.
To the advanced side To advance the closing timing of the intake
valve in order to improve the volumetric
efficiency.
To the retarded side To retard the closing timing of the intake
valve in order to improve the volumetric
efficiency.
Most retarded To shorten the valve opening overlap in
order to prevent the exhaust gas counter
flow to intake manifold and reduce the fuel
increasing.
To slow the fast idle speed of the engine as
a result of stabilizing the engine idling.
Most retarded To shorten the valve opening overlap in
order to prevent the exhaust gas counter
flow to intake manifold.
TARGET OF CONTROL
I3RH0B140007-01
EFFECT
Stabilization of the
engine rotation at idle
speed.
Improvement of the fuel
efficiency.
Lowering of the exhaust
emission.
Keeping of the engine
stability.
Improvement of
generating the engine
torque at low and
average engine speed.
Improvement of
generating the engine
power.
Stabilization of the fast
idling of the engine.
Improvement of the fuel
efficiency.
Improvement of start
ability