2000 LEXUS GS400 engine

EM0D1±05
A11132
Compression Tester
± ENGINE MECHANICAL (2JZ±GE)COMPRESSION
EM±3
1357 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
COMPRESSION
INSPECTION
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 temperature.
2. REMOVE ENGINE COVER
Remove the 4 nuts and engine cover.
3. DISCONNECT IGNITION COILS AND HIGH±TENSION
CORD SET ASSEMBLY (See page IG±7)
4. REMOVE SPARK PLUGS
5. DISCONNECT INJECTOR CONNECTORS
6. CHECK CYLINDER COMPRESSION
(a) Insert a compression tester into the spark plug hole.
(b) While cranking the engine, measure the compression
pressure.
HINT:
Always use a fully charged battery to obtain engine revolutions
of 250 rpm or more.
(c) Repeat steps (a) through (b) for each cylinder.
NOTICE:
This measurement must be done in as short a time as pos-
sible.
Compression:
1,324 kPa (13.5 kgf/cm
2, 192 psi) or more
Minimum pressure:
1,079 kPa (11.0 kgf/cm
2, 156 psi)
Difference between each cylinder:
98 kPa (1.0 kgf/cm
2, 14 psi) or less
(d) If the cylinder compression in 1 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 (b) for
the cylinder with low compression.

If adding oil helps the compression, it is likely that
the piston rings and/or cylinder bore are probably
worn or damaged.

If pressure stays low, a valve may be sticking or
seating improper, or there may be leakage past the
gasket.

EM±4
± ENGINE MECHANICAL (2JZ±GE)COMPRESSION
1358 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
7. RECONNECT INJECTOR CONNECTORS
HINT:
The Nos.1, 3, 5 injector connectors and dark gray, and the
Nos.2, 4, 6 injector connectors are brown.
8. REINSTALL SPARK PLUGS
9. RECONNECT IGNITION COILS AND HIGH±TENSION
CORD SET ASSEMBLY (See page IG±9)
10. INSTALL ENGINE COVER
Install the engine cover with the 4 nuts.

EM0DA±03
A02823
A02802
B01935
Wire
Grommet
Clamp
± ENGINE MECHANICAL (2JZ±GE)CYLINDER HEAD
EM±33
1387 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
REMOVAL
1. REMOVE ENGINE UNDER COVER
2. DRAIN ENGINE COOLANT
3. DISCONNECT UPPER RADIATOR HOSE FROM WA-
TER OUTLET
4. REMOVE ENGINE COVER
Remove the 4 nuts and engine cover.
5. REMOVE AIR CLEANER INLET
6. REMOVE AIR CLEANER, MAF METER AND INTAKE
AIR RESONATOR ASSEMBLY (See page EM±62)
7. REMOVE DRIVE BELT (See page CH±1)
8. DISCONNECT PS PUMP WITHOUT DISCONNECTING
HOSES
(a) Disconnect the PS air hose from the No.4 timing belt cov-
er.
(b) Disconnect the PS air hose from the air intake chamber.
(c) Remove the 2 bolts and pump rear stay.
(d) Remove the 2 bolts, and disconnect the vane pump from
the pump bracket.
HINT:
Put aside the vane pump, and suspend it.
9. DISCONNECT FRONT EXHAUST PIPE FROM EX-
HAUST MANIFOLD
(a) Disconnect the wire grommet and sensor wire of the
heated oxygen sensor (bank 2 sensor 2) from the hole
and clamp on the floor.

A02819
A09752
A02735
EM±34
± ENGINE MECHANICAL (2JZ±GE)CYLINDER HEAD
1388 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
(b) Remove the 3 bolts and nuts holding the front exhaust
pipe to the exhaust manifold.
(c) Remove the 2 bolts and pipe support bracket.
(d) Disconnect the front exhaust pipe from the exhaust man-
ifold, and remove the 2 gaskets.
10. REMOVE EXHAUST MANIFOLD
(a) Disconnect the 3 heated oxygen sensor connectors and
clamp.
(b) Remove the clamp and case clamp.
(c) Using a 14 mm deep socket wrench, remove the 8 nuts,
exhaust manifold and 2 gaskets.
11. REMOVE WATER BYPASS OUTLET AND NO.1
WATER BYPASS PIPE (See page CO±11)
12. REMOVE THROTTLE BODY AND INTAKE AIR
CONNECTOR ASSEMBLY (See page EM±5)
13. REMOVE OIL DIPSTICK AND GUIDE FOR ENGINE
(See page LU±6)
14. REMOVE OIL DIPSTICK AND GUIDE FOR A/T
(See page EM±62)
15. REMOVE AIR INTAKE CHAMBER (See page SF±46)
16. REMOVE VACUUM CONTROL VALVE SET AND NO.2
VACUUM PIPE
(a) Disconnect the VSV connector for the ACIS.
(b) Remove the 3 nuts, vacuum control valve set and No.2
vacuum pipe.
(c) Disconnect the engine wire clamp from the clamp bracket
of the No.2 vacuum pipe.
17. REMOVE NO.3 TIMING BELT COVER
18. REMOVE IGNITION COILS AND HIGH±TENSION
CORD SET ASSEMBLY (See page IG±7)
19. REMOVE SPARK PLUGS

A02732
(a)
(b) (c)
(d)(d)
(c) (b)
A02811
A02733
Clamp Bracket
A11123
5 mm
Hexagon
Wrench
± ENGINE MECHANICAL (2JZ±GE)CYLINDER HEAD
EM±35
1389 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
20. DISCONNECT ENGINE WIRE FROM CYLINDER HEAD
(a) Disconnect the ground strap from the cylinder head.
(b) Disconnect the 2 water bypass hoses from the hose
clamps on the cylinder head and oil filter bracket.
(c) Remove the 2 bolts and hose clamps.
(d) Disconnect the heated oxygen sensor (bank 2 sensor 1)
connector and engine wire clamp from the hose clamps.
(e) Disconnect the heated oxygen sensor (bank 1 sensor 1)
connector.
(f) Disconnect the crankshaft position sensor connector.
(g) Disconnect the generator connector.
(h) Remove the bolt and clamp bracket, and disconnect the
engine wire from the water pump.
(i) Disconnect the 2 ground terminals from the intake man-
ifold.
(j) Disconnect the 2 engine wire clamps from the No.1 oil
pipe and clamp bracket on the intake manifold.
(k) Remove the bolt and clamp bracket.
(l) Disconnect the ECT sensor connector.
(m) Remove the 2 knock sensor connectors.
(n) Remove the oil pressure switch connector.
(o) Remove the oil level sensor connector.
(p) Remove the starter connector.
(q) Remove the 6 injector connectors.
(r) Remove the camshaft timing oil control valve connector.
(s) Remove the camshaft position sensor connector.
(t) Using a 5 mm hexagon wrench, remove the bolt holding
the engine wire protector to the No.2 cylinder head cover.
(u) Remove the 3 nuts, and disconnect the engine wire pro-
tector from the intake manifold.
21. REMOVE FUEL PRESSURE PULSATION DAMPER
(See page SF±26)

A11122
A02713
A02836
S03013
A02647
EM±36
± ENGINE MECHANICAL (2JZ±GE)CYLINDER HEAD
1390 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
22. REMOVE INTAKE MANIFOLD ASSEMBLY
(a) Disconnect the starter wire from the manifold stay.
(b) Remove the 2 bolts and manifold stay.
(c) Remove the 7 bolts, 2 nuts, intake manifold and delivery
pipe assembly and gasket.
23. REMOVE NO.1 AND NO.2 CYLINDER HEAD COVERS
(a) Remove the 12 bolts and 4 nuts.
(b) Remove the cylinder head covers and gaskets.
24. DISCONNECT TIMING BELT FROM CAMSHAFT TIM-
ING PULLEYS (See page EM±16)
NOTICE:

Support the timing belt, so that the measuring of the
crankshaft timing pulley and timing belt does not
shift.

Be careful not to drop anything inside the timing belt
cover.

Do not allow the timing belt to come into contact with
oil, water or dust.
25. REMOVE CAMSHAFT TIMING PULLEYS
(a) Remove the exhaust camshaft timing pulley.
Hold the hexagon portion of the camshaft with a wrench, and
remove the pulley bolt and camshaft pulley.
(b) Remove the VVT±i (intake camshaft timing) pulley.
(See page EM±16)
26. REMOVE NO.4 TIMING BELT COVER
Remove the 4 bolts and timing belt cover.

A02695
5 mm Hexagon
Wrench
A02696
No.1
No.3
A02930
110
211
12
5
67
83
49
1
2
11
12
5
6
7
8
3
4910
S02650
10 mm
Bi±Hexagon
Wrench
3
14 12 13 10 11 762
15 9 8 4
± ENGINE MECHANICAL (2JZ±GE)CYLINDER HEAD
EM±37
1391 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
27. REMOVE CAMSHAFTS
(a) Using a 5 mm hexagon wrench, the 2 No.3 camshaft
bearing cap bolts.
(b) Uniformly loosen and remove the 4 camshaft bearing cap
bolts.
(c) Using a screwdriver, pry out the Nos.1, 3 camshaft bear-
ing caps and oil seals.
NOTICE:
Be careful not to damage the cap. Tape the screwdriver tip.
(d) Uniformly loosen and remove the 12 camshaft bearing
cap bolts, in several passes, in the sequence shown.
(e) Remove the 6 No.2 camshaft bearing caps and camshaft.
Remove the intake and exhaust camshafts.
28. REMOVE CYLINDER HEAD ASSEMBLY
(a) Using a 10 mm bi±hexagon wrench, uniformly loosen and
remove the 14 cylinder head bolts, in several passes, in
the sequence shown.
NOTICE:
Cylinder head warpage or cranking could result from re-
moving in incorrect order.
(b) Remove the 14 plate washers.

S03016
Lift
Pry EM±38
± ENGINE MECHANICAL (2JZ±GE)CYLINDER HEAD
1392 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
(c) Lift the cylinder head from the dowels on the cylinder
block.
(d) Disconnect the heater hose from the heater union.
(e) Place the head on wooden blocks on a bench.
If the cylinder head is difficult to lift off, pry with a screwdriver be-
tween the cylinder head and block projection.
NOTICE:
Be careful not to damage the contact surfaces of the cylin-
der head and cylinder block.