Measurement of Compression Pressure
1. Warm up engine.
2. Turn ignition switch OFF.
3. Release fuel pressure.
Refer to EC section (``Fuel Pressure Release'', ``BASIC SER-
VICE PROCEDURE'').
4. Remove all spark plugs.
5. Disconnect distributor center cable.
6. Attach a compression tester to No. 1 cylinder.
7. Depress accelerator pedal fully to keep throttle valve wide
open.
8. Crank engine and record highest gauge indication.
9. Repeat the measurement on each cylinder.
lAlways use a fully-charged battery to obtain specified
engine speed.
Compression pressure:
kPa (bar, kg/cm
2, psi)/rpm
Standard
1,324 (13.24, 13.5, 192)/300
Minimum
981 (9.8, 10, 142)/300
Difference limit between cylinders
98 (0.98, 1.0, 14)/300
10. If compression in one or more cylinders is low:
a. Pour a small amount of engine oil into cylinders through
spark plug holes.
b. Retest compression.
lIf adding oil helps compression, piston rings may be
worn or damaged. If so, replace piston rings after check-
ing piston.
lIf pressure stays low, a valve may be sticking or seating
improperly. Inspect and repair valve and valve seat.
(Refer to SDS.) If valve or valve seat is damaged
excessively, replace them.
lIf compression stays low in two cylinders that are next
to each other:
a. The cylinder head gasket may be leaking, or
b. Both cylinders may have valve component damage.
Inspect and repair as necessary.
SEM113B
COMPRESSION PRESSUREKA
EM-10
