Lexus ES300 (1997 year). Service manual — part 481

IG023–02

CHECK POWER SUPPLY OF HIGH–TENSION COIL AND IGNITER

SPARK TEST

Replace the camshaft position sensor.

CHECK RESISTANCE OF HIGH–TENSION CORD

Maximum resistance: 25 k

Ω

per cord

CHECK RESISTANCE OF IGNITION COIL

1. Turn ignition switch to ON.
2. Check that there is battery voltage at ignition

coil positive (+) terminal.

CHECK CONNECTION OF IGNITION COIL AND IGNITER

Resistance:

Cold

Hot

Secondary

10.8 – 14.9 k

Ω

13.1 – 17.5 k

Ω

CHECK RESISTANCE OF CAMSHAFT POSITION SENSOR

Resistance:

Cold

Hot

835 – 1,400

Ω

1,060 – 1,645

Ω

CHECK IGT SIGNAL FROM ECM

CHECK RESISTANCE OF CRANKSHAFT POSITION SENSOR

Resistance:

Cold

Hot

1,630 – 2,740

Ω

2,065 – 3,225

Ω

TRY ANOTHER IGNITER

Replace the crankshaft position sensor.

Replace the ignition coil (s).

Connect securely.

Replace the cord(s).

Check wiring between ignition switch to
ignition coil and igniter.

Check wiring between ECM and igniter, and
then try another ECM.

NO

OK

OK

OK

OK

OK

OK

BAD

BAD

BAD

BAD

BAD

BAD

BAD

CONNECTORS

Primary

0.70 – 0.94

Ω

0.85 – 1.10

Ω

OK

–

IGNITION

IGNITION SYSTEM

IG–1

972

1997 LEXUS ES300 (RM511U)

IGNITION SYSTEM

ON–VEHICLE INSPECTION

NOTICE:
”Cold” and ”Hot” in these sentences express the tempera-
ture of the coils themselves. ”Cold” is from –10

°

C (14

°

F) to

50

°

C (122

°

F) and ”Hot” is from 50

°

C (122

°

F) to 100

°

C

(212

°

F).

1.

INSPECT IGNITER SPARK TEST

Check that the spark occurs.

(1)

Remove the ignition coil.

(2)

Remove the spark plug.

(3)

Install the spark plug to the ignition coil, and connect
the ignition coil connector.

(4)

Ground the spark plug.

(5)

Check if spark occurs while engine is being
cranked.

NOTICE:
To prevent excess fuel being injected from the injectors
during this test, do not crank the engine for more 5 – 10 se-
conds at a time.
If the spark does not occur, do the test as follows:

P25767

P24453

WRONG

CORRECT

P24457

P25722

(1)

(2)

IG–2

–

IGNITION

IGNITION SYSTEM

973

1997 LEXUS ES300 (RM511U)

2.

INSPECT HIGH–TENSION CORDS

(a)

Remove the V–bank cover.

(b)

Disconnect the high–tension cords from the spark plugs.
(1)

Using needle–nose pliers, disconnect the cord
clamp from the engine wire protector.

(2)

Disconnect the high–tension cords from the spark
plugs.

NOTICE:
Pulling on or bending the cords may damage the conductor
inside.

(3)

Disconnect the high–tension cords from the clamp.

(c)

Disconnect the high–tension cords from the ignition coils.
(1)

Using a screwdriver, lift up the lock claw and discon-
nect the holder from the ignition coils.

(2)

Disconnect the high–tension cord at the grommet.

HINT:
Do not pull on the cord.
NOTICE:

Pulling on or bending the cords may damage the con-
ductor inside.

Do not wipe any of the oil from the grommet after the
high–tension cord is disconnected.

(d)

Remove the high–tension cords set.
(1)

Disconnect the clamp from the emission control
valve set.

(2)

Remove the high–tension cords set in indicated
direction.

P25768

Ohmmeter

S06106

P24458

Holder

Grommet

–

IGNITION

IGNITION SYSTEM

IG–3

974

1997 LEXUS ES300 (RM511U)

(e)

Using an ohmmeter, measure the resistance.
Maximum resistance: 25 k

Ω

per cord

If the resistance is greater than maximum, check the terminals.
If necessary, replace the high–tension cord.
(f)

Install the high–tension cords set.

(g)

Connect the high–tension cords to the ignition coils.
(1)

Assemble the holder and grommet.

(2)

Align the spline of the ignition coil with the spline of
the holder, and push in the cord.

S00813

CORRECT

WRONG

Clearance

IG0147

Megger

Ground

P13225

16 mm Plug
Wrench

P25746

DENSO PK20TR11

NGK BKR6EKPB11

IG–4

–

IGNITION

IGNITION SYSTEM

975

1997 LEXUS ES300 (RM511U)

NOTICE:
Check that the holder is correctly installed to the grommet
and ignition coil as shown in the illustration.

(3)

Check that the lock claw of the holder is engaged by
lightly pulling the holder.

(h)

Connect the high–tension cords to the spark plugs.

(i)

Install the V–bank cover.

3.

INSPECT SPARK PLUGS

NOTICE:

Never use a wire brush for cleaning.

Never attempt to adjust the electrode gap on a used
spark plug.

Spark plugs should be replaced every 100,000 km
(60,000 miles).

(a)

Remove the ignition coil.

(b)

Inspect the electrode.
Using a megger (insulation resistance meter), measure
the insulation resistance.
Standard correct insulation resistance:
10 M

Ω

or more

If the resistance is less than specified, proceed to step (e).
HINT:
If a megger is not available, the following simple method of in-
spection provides fairly accurate results.

(c)

Simple Method:
(1)

Quickly race the engine to 4,000 rpm 5 times.

(2)

Remove the spark plug. (See step (d))

(3)

Visually check the spark plug.

If the electrode is dry ... OK
If the electrode is wet ... Proceed to step (e)

(4)

Install the spark plug. (See step (h))

(d)

Using a 16 mm plug wrench, remove the 6 spark plugs
from the RH and LH cylinder heads.

(e)

Check the spark plug for thread damage and insulator
damage.

If abnormal, replace the spark plug.

Recommended spark plug:

DENSO

PK20TR11

NGK

BKR6EKPB11