Page 4 of 2000

ENGINE - 2AZ-FE ENGINE
DR011EG22 01NEG26Y
Air Flow During Engine Revolution
Wa t e r P u m p
Swirl Chamber
Crankshaft
Bearing Cap
Plastic Region
Tightening BoltsThermostat Housing
Air Conditioning
Compressor BracketsAir Passage Holes
Air Flow
NOTICE
Never attempt to machine the cylinder because it has a thin liner thickness.
EG-7
4. Cylinder Block
Lightweight aluminum alloy is used for the cylinder block.
By producing the thin cast-iron liners and cylinder block as a unit, compaction is realized.
Air passage holes are provided in the crankshaft bearing area of the cylinder block. As a result, the air at
the bottom of the cylinder flows smoother, and pumping loss (back pressure at the bottom of the piston
generated by the piston’s reciprocal movement) is reduced to improve the engine’s output.
The oil filter and the air conditioning compressor brackets are integrated into the crankcase. Also, the
water pump swirl chamber and thermostat housing are integrated into the cylinder block.
Page 5 of 2000
ENGINE - 2AZ-FE ENGINE
01NEG27Y
Irregularly shaped
outer casting
surface of linerCylinder Block
Liner A
A
A - A Cross Section
01NEG28Y
Water Jacket
Spacer Water Jacket
A - A Cross Section A
A EG-8
The liners are the spiny-type, which have been manufactured so that their casting exteriors form large
irregular surfaces in order to enhance the adhesion between the liners and the aluminum cylinder block.
The enhanced adhesion helps heat dissipation, resulting in a lower overall temperature and heat
deformation of the cylinder bores.
Water jacket spacers are provided in the water jacket of the cylinder block.
They suppress the water flow in the center of the water jackets, guide the coolant above and below the
cylinder bores, and ensure uniform temperature distribution. As a result, the viscosity of the engine oil that
acts as a lubricant between the bore walls and the pistons can be lowered, thus reducing friction.
Page 7 of 2000
ENGINE - 2AZ-FE ENGINE
01NEG31Y
No.1 JournalBalance Shaft Drive Gear
Oil Hole
Crank Pin
Balance Weight
01NEG32Y
: Resin Gear
Balance Shaft
HousingBalance Shaft No.1 Balance Shaft No.2Crankshaft
Balance Shaft Drive Gear EG-10
7. Crankshaft
The forged crankshaft has 5 journals and 8 balance weights.
The crankshaft is made of forged steel.
Pin and journal fillets are roll-finished to maintain adequate strength.
The balance shaft drive gear is provided for the crankshaft.
8. Balance Shaft
General
A balance shaft is used to reduce vibrations.
The crankshaft directly drives the No. 1 balance shaft.
In addition, a resin gear is used on the driven side to suppress noise and offer lightweight design.
Page 10 of 2000

ENGINE - 2AZ-FE ENGINE
181EG11
VVT-i ControllerIntake CamshaftTiming Rotor
Exhaust Camshaft
Timing Sprocket
185EG25 181EG14
Cam Spring
Cam
Plunger
SpringChain
Te n s i o n e r
Chain Damper
Oil Jet
Chain TensionerChain SlipperEG-13
2. Camshaft
The intake camshaft is provided with timing rotor to trigger the camshaft position sensor.
In conjunction with the adoption of the VVT-i system, an oil passage is provided in the intake camshaft
in order to supply engine oil pressure to the VVT-i system.
A VVT-i controller has been installed on the front of the intake camshaft to vary the timing of the intake
valves.
3. Timing Chain
A roller chain with an 8 mm (0.315 in.) pitch is used to make the engine more compact.
The timing chain is lubricated by an oil jet.
The chain tensioner uses a spring and oil pressure to maintain proper chain tension at all times.
The chain tensioner suppresses noise generated by the timing chain.
A ratchet type non-return mechanism is used.
To achieve excellent serviceability, the chain tensioner is constructed so that it can be removed and
installed from the outside of the timing chain cover.
Page 11 of 2000
ENGINE - 2AZ-FE ENGINE
208EG07
VVT-i Controller
Camshaft Timing
Oil Control Valve
Oil Return
Hole
Oil PumpOil Filter Chain
Te n s i o n e r
01NEG33Y
Bypass
Va l v e
Relief
Va l v eMain Oil Hole
Oil Filter
Oil Pump
Oil StrainerChain
Te n s i o n e rCylinder Head
Exhaust
Camshaft
Journal
Oil Control
Va l v e
VVT-i Controller
Oil Pan
Intake
Camshaft
Journal
Crankshaft
Journal
Crankshaft
Pin
Oil Jet
Piston
Cylinder
Block
Barance
Shaft
Timing
Chain EG-14
LUBRICATION SYSTEM
1. General
The lubrication circuit is fully pressurized and oil passes through an oil filter.
The trochoid gear type oil pump is chain-driven by the crankshaft.
The oil filter is attached downward from the crankcase to improve serviceability.
Along with the adoption of the VVT-i system, the cylinder head is provided with a VVT-i controller and
a camshaft timing oil control valve. This system is operated by the engine oil.
Oil Circuit
Page 12 of 2000
ENGINE - 2AZ-FE ENGINE
01NEG34Y
Oil Jets
Check
Va l v e
Oil
Bottom Side View Oil Jet Cross SectionEG-15
Oil Capacity
Liters (US qts, Imp. qts)
Dry
5.0 (5.3, 4.4)
with Oil Filter4.3 (4.5, 3.8)
without Oil Filter4.1 (3.8, 3.1)
2. Oil Jet
Piston oil jets for cooling and lubricating the pistons are used in the cylinder block.
These oil jets contain a check valve to prevent oil from being fed when the oil pressure is low. This prevents
the overall oil pressure in the engine from dropping.
Page 21 of 2000
ENGINE - 2AZ-FE ENGINE
165EG25
Camshaft
Position
Sensor
Crankshaft
Position
Sensor
Va r i o u s
SensorG2
NE
ECMIGT1
IGT2
IGT3
IGT4
IGF+BIgnition Coil
(with Igniter)
No.1 Cylinder
No.2 Cylinder
No.3 Cylinder
No.4 Cylinder
185EG38
0.7 mm
(0.028 in.)
Iridium Tip EG-24
IGNITION SYSTEM
1. General
A DIS (Direct Ignition System) is used. The DIS improves the ignition timing accuracy, reduces
high-voltage loss, and enhances the overall reliability of the ignition system by eliminating the distributor.
The DIS in this engine is an independent ignition system which has one ignition coil (with igniter) for each
cylinder.
Iridium-tipped spark plugs are used.
2. Spark Plug
Iridium-tipped spark plugs are used to improve ignition performance while maintaining the same durability
of the platinum-tipped spark plugs.
Specifications
DENSOSK20R11
NGKIFR6A11
Plug Gap1.0 - 1.1 mm
(0.039 - 0.043 in.)
Page 23 of 2000
ENGINE - 2AZ-FE ENGINE
01NEG45Y
RegulatorB
M
IG
RLO
L
Ignition Switch
To Discharge
Wa r n i n g L i g h t
Generator
ECM
281EG13
281EG12
Coil SpringPulley
Helical Coil Type One-way Clutch EG-26
Wiring Diagram
2. Generator Pulley
A helical coil type one-way clutch is used on the generator pulley in order to reduce the load that acts on
the auxiliary equipment belt.
The pulley mounting nut and the generator pulley have been integrated to achieve a compact construction.