Diagnostic Information And Procedures; Compression Check - Suzuki SX4 Service Manual

Targeted Timing Varying Operation
Driving condition
Engine running at idle
Most retarded
speed
Average engine load To the advanced
range side
Light engine load
To the retarded side
range
Low or average
engine speed range To the advanced
with heavy engine side
load
High engine speed
range with heavy To the retarded side
engine load
Low engine coolant
Most retarded
temperature
At engine starting and
Most retarded
stopping

Compression Check

Check compression pressure on all 4 cylinders as
follows:
1) Warm up engine to normal operating temperature.
2) Stop engine after warming up.
NOTE
After warming up engine, place transmission
gear shift lever in "Neutral" (shift selector
lever to "P" range for A/T model), and set
parking brake and block drive wheels.
3) Remove air cleaner assembly with air suction hose
referring to "Air Cleaner Assembly Removal and
Installation".
4) Remove cylinder head upper cover.
5) Remove ignition coil assemblies and all spark plugs
referring to "Spark Plug Removal and Installation in
Section 1H".
6) Disconnect fuel injector wires at the coupler.
Valve timing
To shorten the valve opening overlap in
order to prevent the exhaust gas
counterflow to intake manifold.
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
counterflow to intake manifold.
To advance the closing timing of the
intake valve in order to improve the
volumetric efficiency.
To retard the closing timing of the
intake valve in order to improve the
volumetric efficiency.
To shorten the valve opening overlap in
order to prevent the exhaust gas
counterflow 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.
To shorten the valve opening overlap in
order to prevent the exhaust gas
counterflow to intake manifold.

Diagnostic Information and Procedures

S7RW0A1404001
Target of control
7) Install special tools (Compression gauge) into spark
plug hole.
Special tool
(A): 09915–64512
(B): 09915–64530
(C): 09915–67010
(C)
Engine Mechanical:
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.
(A)
(B)
I3RH0B140009-01
1D-5