4A–FE engine is an in–line, 4–cylinder, 1.6 liter DOHC 16–valve engine. Manual — part 4

INSPECTION AND ADJUSTMENT OF
IGNITION TIMING
4A–FE (See page

IG–25

)

3S–GTE (See page

IG–29

)

5S–FE (See page

IG–37

)

Ignition timing:

10

В°

BTDC @ idle

(w/ Terminals TE1 and E1 connected)

INSPECTION AND ADJUSTMENT OF IDLE
SPEED (4A–FE)

(See page

MA–8

)

Idle speed: 800 rpm

INSPECTION OF IDLE SPEED (5S–FE and
3S–GTE)

HINT (5S–FE): Disconnecting the battery will cause the
idling speed data in the ISC to be returned to the initial
idling speed, causing the idling speed to rise above
750 rpm. Should this happen, either carry out a driving
test, including stop–go several times at a speed above
10 km/h (6 mph), or start the engine, idle for 30 seconds
and then turn the engine oft repeatedly. By doing this,
idle data will be stored in the ISC and the idle rpm will
be at specified value.

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 vacuum lines connected
HINT: All vacuum hoses for EGR systems, etc. should
be properly connected.
(e) EFI system wiring connectors fully plugged
(f) All operating accessories switched OFF
(g) Transmission in neutral position

2. CONNECT TACHOMETER

Connect the test probe of a tachometer to terminal
IG (–) of the check connector.
NOTICE:

•

Never allow the tachometer terminal to touch
ground as it could result in damage to the igniter
and/or ignition coil.

•

As some tachometers are not compatible with
this ignition system, we recommend that you
confirm the compatibility of your unit before
use.

–

ENGINE MECHANICAL

Engine Tune–Up

EM–26

(b) Check the idle speed.

Idle speed:

3S–GTE 800

В±

50 rpm

5S–FE 700

В±

50 rpm USA

750

В±

50 rpm CANADA

If the idle speed is not as specified, check the ISC
system.

4. DISCONNECT TACHOMETER

3. INSPECT IDLE SPEED

(a) Race the engine at 2,500 rpm for approx. 90
seconds.

–

ENGINE MECHANICAL

Engine Tune–Up

EM–27

TOYOTA–VARIABLE INDUCTION
SYSTEM (T–VIS)

INSPECTION OF T–VIS

1. WARM UP AND STOP ENGINE

Allow the engine to warm up to normal operating tem-
perature.

2. CONNECT TACHOMETER (See page

EM–26

)

(b) Check that the vacuum gauge indicates zero at

4,200 rpm or more.
HINT: If regular unleaded gasoline is used, the vacuum
gauge also indicates zero below 4,200 rpm.

4. INSPECT T–VIS OPERATION

(a) Check that the vacuum gauge indicates vacuum at

idling.

3. CONNECT VACUUM GAUGE

Using a 3–way connector, connect the vacuum gauge to
the hose between the VSV and actuator.

–

ENGINE MECHANICAL

TOYOTA–Variable Induction System (T–VIS) (3S–GTE)

EM–28

IDLE AND OR 2500 RPM CO HC
CHECK

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
HINT: All vacuum hoses for EGR systems, etc. should
be properly connected.
(f) EFI system wiring connectors fully plugged
(g) Ignition timing set 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. 120

(4A–FE AND 3S–GTE) OR 180 (5S–FE) SECONDS

4. INSERT CO/HC METER TESTING PROBE INTO TAILPIPE

AT LEAST 40 cm 0.3 ft) DURING IDLING

5. IMMEDIATELY CHECK CO/HC CONCENTRATION AT

IDLE AND/OR 2,500 RPM
Complete the measuring within three minutes.
HINT: When performing the 2 mode (2,500 prm and
idle) test, follow the measurement order prescribed by
the applicable local regulations.
(4A–FE and 3S–GTE)
If the CO/HC concentration at 2,500 rpm does not con-
form to regulations, try the following procedure.
Race the engine again at 2,500 rpm for approx. 1
minute and quickly repeat steps 4 and 5 above. This
may correct the problem.

–

ENGINE MECHANICAL

Idle and or 2500 rpm CO HC Check

EM–29

Troubleshooting

If the CO/HC concentration does not comply with regu-
lations, perform troubleshooting in the order given be–
low.
(a) Check oxygen sensor operation.

(See page

FI–237

)

(b) See the table below for possible causes, and then

inspect and correct the applicable causes if neces-
sary.

1. Faulty ignitions:

•

Incorrect timing

•

Fouled, shorted or improperly gapped plugs

•

Open or crossed high–tension cords

•

Cracked distributor cap

2. Incorrect valve clearance
3. Leaky EGR valve
4. Leaky intake and exhaust valves
5. Leaky cylinder

1. Restricted air filter
2. Faulty EFI systems:

•

Faulty pressure regulator

•

Clogged fuel return line

•

Defective water temp. sensor

•

Defective air temp. sensor

•

Faulty ECU

•

Faulty injectors

•

Faulty cold start injector (3S–GTE)

•

Faulty throttle position sensor

•

Vacuum sensor (4A–FE and 5S–FE)

•

Air flow meter (3S–GTE)

1. Vacuum leaks:

•

PCV hoses

•

EGR valve

•

Intake manifold

•

T–VIS valve (3S–GTE)

Throttle body

ISC valve (3S–GTE and 5S–FE)

Brake booster line

2. Lean mixture causing misfire

Rough idle

(Black smoke from exhaust)

Rough idle

(Fluctuating HC reading)

Rough idle

Problems

Normal

Causes

High

High

High

High

Low

–

ENGINE MECHANICAL

Idle and or 2500 rpm CO HC Check

EM–30

7. 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:

4A–FE

1,320 kPa (13.5 kgf/cm

2

, 191 psi) or more

3S–GTE 1,128 kPa (11.5 kgf/cm

2

, 164 psi)

or more

5S–FE

1,226 kPa (12.5 kgf/cm

2

, 178 psi)

or more

Minimum pressure:

4A–FE and 5S–FE

981 kPa (10.0 kgf /cm

2

, 142 psi )

3S–GTE 883 kPa (9.0 kgf/cm

2

, 128 psi)

Difference between each cylinder:

98 kPa (1.0 kgf/cm

2

, 14 psi) or less

COMPRESSION CHECK

HINT: If there is lack of power, excessive oil consump-
tion or poor fuel economy, measure the compression
pressure.

1. WARM UP AND STOP ENGINE

Allow the engine to warm up to normal operating tem-
perature.

2. (3S–GTE)

REMOVE INTERCOOLER
(See steps 13 to 15 on pages

TC–9

and 10)

3. (3S–GTE)

DISCONNECT SOLENOID RESISTOR CONNECTOR

4. (3S–GTE)

DISCONNECT COLD START INJECTOR CONNECTOR

5. DISCONNECT DISTRIBUTOR CONNECTOR(S)
6. REMOVE SPARK PLUGS

–

ENGINE MECHANICAL

Compression Check

EM–31

(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 compres-
sion.

•

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.

8. REINSTALL SPARK PLUGS

Torque: 18 N–m (180 kgf–cm, 13 ft–lbf)

9. RECONNECT DISTRIBUTOR CONNECTOR(S)
10. (3S–GTE)

RECONNECT COLD START INJECTOR CONNECTOR

11. (3S–GTE)

RECONNECT SOLENOID RESISTOR CONNECTOR

12. (3S–GTE)

REINSTALL INTERCOOLER
(See steps 11 to 13 on page

TC–17

)

–

ENGINE MECHANICAL

Compression Check

EM–32

REMOVAL OF TIMING BELT

1. DISCONNECT CABLE FROM NEGATIVE TERMINAL

OF BATTERY
CAUTION: Work must be started after approx. 20

seconds or longer from the time the ignition switch is

turned to the ”LOCK” position and the negative (–) ter–

minal cable is disconnected from the battery.

2. REMOVE RH FRONT WHEEL
3. REMOVE RH ENGINE UNDER COVER
4. REMOVE ALTERNATOR DRIVE BELT

(a) Loosen the four water pump pulley bolts.

TIMING BELT (4A–FE)

COMPONENTS

–

ENGINE MECHANICAL

Timing Belt (4A–FE)

EM–33