2001 TOYOTA AVALON Service Repair Manual

EC04T-03
B07459
N´m (kgf´cm, ft´lbf) : Specified torque
 Non-reusable part Gasket
44 (450, 33)
Damper  Gasket
43 (440, 32)
TWC
Compression Spring
Center Exhaust PipeCompression Spring
43 (440, 32)
Heated Oxygen Sensor
(Bank 1 Sensor 2)
Heated Oxygen Sensor (Bank 1 Sensor 2)
HINT:

Before installing the heated oxygen sensor,
twist the sensor wire counterclockwise
3 and 1/2 turns.

After installing the heated oxygen sensor,
check that the sensor wire is not twisted,
if it is twisted, remove the heated oxygen
sensor and reinstall it.
- EMISSION CONTROLTHREE-W AY CATALYTIC CONVERTER (TWC)
SYSTEMEC-15
1109 Author
: Date
:
2001 AVALON (RM808U)
COMPONENTS

EC04S-01
EC-14- EMISSION CONTROLTHREE-W AY CATALYTIC CONVERTER (TWC)
SYSTEM
1108 Author
: Date
:
2001 AVALON (RM808U)
THREE-W AY CATALYTIC CONVERTER (TWC) SYSTEM
ON-VEHICLE INSPECTION
1. INSPECT EXHAUST PIPE ASSEMBLY
(a) Check the connections for looseness or damage.
(b) Check the clamps for weakness, cracks or damage.
2. INSPECT TWC
Check for dents or damage.
If any part of the protector is damaged or dented to the extent that it contacts the TWC, repair or replace
it.
3. INSPECT TWC HEAT INSULATOR
(a) Check the heat insulator for damage.
(b) Check for adequate clearance between the catalytic converter and heat insulator.

EC0BI-02
B07452
N´m (kgf´cm, ft´lbf) : Specified torque

Non-reusable part
Gasket
62 (630, 46)
43 (440, 32)

Gasket


62 (630, 46)
33 (330, 24)
WU-TWC for Bank 1

Front Exhaust Pipe WU-TWC
Stay

Gasket
Compression Spring
EC-12- EMISSION CONTROLWARM UP THREE-W AY CATALYTIC CONVERTER
(WU-TWC) SYSTEM
1106 Author
: Date
:
2001 AVALON (RM808U)
COMPONENTS

B07458
WU-TWC for Bank 2
LH Exhaust Manifold
(with WU-TWC)
LH Exhaust Manifold
Heat InsulatorA/F Sensor Connector
A/F Sensor
LH Exhaust Manifold Stay
Gasket
Gasket
49 (500, 63)
62 (630, 46)
44 (450, 33)
x 6


N´m (kgf´cm, ft´lbf) : Specified torque

Non-reusable part
- EMISSION CONTROLWARM UP THREE-W AY CATALYTIC CONVERTER
(WU-TWC) SYSTEMEC-13
1107 Author
: Date
:
2001 AVALON (RM808U)

EC0BH-01
- EMISSION CONTROLWARM UP THREE-W AY CATALYTIC CONVERTER
(WU-TWC) SYSTEMEC-1 1
1105 Author
: Date
:
2001 AVALON (RM808U)
WARM UP THREE-WAY CATALYTIC CONVERTER
(WU-TWC) SYSTEM
ON-VEHICLE INSPECTION
1. INSPECT EXHAUST PIPE ASSEMBLY
(a) Check the connections for looseness or damage.
(b) Check the clamps for weakness, cracks or damage.
2. INSPECT WU-TWC
Check for dents or damage.
If any part of the protector is damaged or dented to the extent that it contacts the WU-TWC, repair or replace
it.
3. INSPECT WU-TWC HEAT INSULATOR
(a) Check the heat insulator for damage.
(b) Check for adequate clearance between the catalytic converter and heat insulator.

EM0CB-03
A10537
CO/HC Meter
- ENGINE MECHANICALCO/HC
EM-1
985 Author
: Date
:
2001 AVALON (RM808U)
CO/HC
INSPECTION
HINT:
This check is used only to determine whether or not the idle CO/
HC complies with regulations.
1. INITIAL CONDITIONS
(a) Engine at normal operating temperature
(b) Air cleaner installed
(c) All pipes and hoses of air induction system connected
(d) All accessories switched OFF
(e) All vacuum lines properly connected
(f) SFI system wiring connectors fully plugged
(g) Ignition timing check correctly
(h) Transmission in neutral position
(i) Tachometer and CO/HC meter calibrated by hand
2. START ENGINE
3. RACE ENGINE AT 2,500 RPM FOR APPROX. 180 SE-
CONDS
4. INSERT CO/HC METER TESTING PROBE AT LEAST
40 cm (1.3 ft) INTO TAILPIPE DURING IDLING
5. IMMEDIATELY CHECK CO/HC CONCENTRATION AT
IDLE AND/OR 2,500 RPM
HINT:
When doing the 2 mode (2,500 rpm and idle) test, follow the
measurement order prescribed by the applicable local regula-
tions.

EM-2
- ENGINE MECHANICALCO/HC
986 Author
: Date
:
2001 AVALON (RM808U)
If the CO/HC concentration does not comply with regulations,
troubleshoot in the order given below.
See the table below for possible causes, and then inspect and
correct the applicable causes if necessary.
COHCProblemsCauses
NormalHighRough idle3. Faulty ignitions:

Incorrect timing

Fouled, shorted or improperly gapped plugs
4. Incorrect valve clearance
5. Leaky intake and exhaust valves
6. Leaky cylinders
LowHighRough idle
(Fluctuating HC reading)1. Vacuum leaks:

PCV hoses

Intake manifold

Air intake chamber

Throttle Body

IAC valve

Brake booster line
2. Lean mixture causing misfire
HighHighRough idle
(Black smoke from exhaust)1. Restricted air filter
2. Plugged PCV valve
3. Faulty SFI systems:

Faulty pressure regulator

Defective ECT sensor

Faulty ECM

Faulty injectors

Faulty throttle position sensor

Faulty MAF meter

EM0CC-03
P19471Compression Gauge
- ENGINE MECHANICALCOMPRESSION
EM-3
987 Author
: Date
:
2001 AVALON (RM808U)
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 IGNITION COILS (See page IG-5)
3. REMOVE SPARK PLUGS
Using a 16 mm plug wrench, remove the 6 spark plugs.
4. 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 pos-
sible.
Compression pressure:
1,500 kPa (15.3 kgf/cm
2, 218 psi)
Minimum pressure:
1,000 kPa (10.2 kgf/cm
2, 145 psi)
Difference between each cylinder:
100 kPa (1.0 kgf/cm
2, 15 psi) or less
(e) 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 (c) for
cylinders with low compression.

If adding oil helps the compression, it is likely 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.
5. REINSTALL SPARK PLUGS
6. INSTALL IGNITION COILS (See page IG-5)