Toyota 2VZ-FE Manual page 16

EM-14
ENGINE MECHANICAL – Compression Check
COMPRESSION CHECK
HINT: If there is lack of power, excessive oil consumption or
poor fuel economy, measure the compression pressure.
1. WARM UP AND STOP ENGINE
Allow the engine to warm up to normal operating tempera-
ture.
2. REMOVE AIR INTAKE CHAMBER
(See steps 1 to 14 on pages
3. DISCONNECT DISTRIBUTOR CONNECTOR
4. REMOVE SPARK PLUGS (See page IG–7)
5. CHECK CYLINDER COMPRESSION PRESSURE
(a) Insert a compression gauge into the spark plug hole.
(b) Fully open the throttle.
(c) While cranking the engine, measure the compression
pressure.
HINT: Always use a fully charged battery to obtain engine
speed of 250 rpm or more.
(d) Repeat steps (a) through (c) for each cylinder.
NOTICE: This measurement must be done in as short a
time as possible.
Compression pressure:
12.5 kg/cm
Minimum pressure:
10.0 kg/cm
Difference between each cylinder:
1.0 kg/cm
(e) If the cylinder compression in one or more cylinders is
low, pour a small amount of engine oil into the cylinder
through the spark plug hole and repeat steps (a) through
(c) for cylinders with low compression.
6. REINSTALL SPARK PLUGS (See page IG–7)
Torque: 180 kg–cm (13 ft–lb, 18 N m)
7. RECONNECT DISTRIBUTOR CONNECTOR
8. REINSTALL AIR INTAKE CHAMBER
(See steps 6 to 20 on pages
FI–28
2
(178 psi, 1226 kPa) or more
2
(142 psi, 981 kPa)
2
(14 psi, 981 kPa) or less
If adding oil helps the compression chances are
that the piston rings and/or cylinder bore are worn
or damaged.
If pressure stays low, a valve may be sticking or
seating is improper, or there may be leakage past
the gasket.
FI–33
and 29)
and 34)