TOYOTA CAMRY 1999 Service Repair Manual

± DIAGNOSTICSENGINE (5S±FE)
DI±89
324 Author: Date:
DTC P0300 Random/Multiple Cylinder Misfire Detected
DTC P0301 Cylinder 1 Misfire Detected
DTC P0302 Cylinder 2 Misfire Detected
DTC P0303 Cylinder 3 Misfire Detected
DTC P0304 Cylinder 4 Misfire Detected
CIRCUIT DESCRIPTION
Misfire: The ECM uses the crankshaft position sensor and camshaft position sensor to monitor changes in
the crankshaft rotation for each cylinder.
The ECM counts the number of times the engine speed change rate indicates that misfire has occurred. And
when the misfire rate equals or exceeds the count indicating that the engine condition has deteriorated, the
MIL lights up.
If the misfire rate is high enough and the driving conditions will cause catalyst overheating, the MIL blinks
when misfiring occurs.
DTC No.DTC Detecting ConditionTrouble Area
P0300Mi fi i f d li d i d t t d d i ti l

Ignition system

Injector

Fuel line pressure

EGR
P0300
P0301
P0302
P0303
P0304
Misfiring of random cylinders is detected during any particular
200 or 1,000 revolutions
For any particular 200 revolutions for engine, misfiring is de-
tected which can cause catalyst overheating
(This causes MIL to blink)

EGR

Compression pressure

Valve clearance not to specification

Valve timing

Manifold absolute pressure sensor
P0304(This causes MIL to blink)
Manifold absolute ressure sensor

Engine coolant temp. sensor

Open or short in engine wire

Connector connection

ECM
HINT:
When the 2 or more codes for a misfiring cylinder are recorded repeatedly but no random misfire code is
recorded, it indicates that the misfires were detected and recorded at different times.
DI011±07

A03626
ECM
#10
#20
#30
#40
E01
E02 Injector
No. 1
No. 2
No. 3
No. 4E9
E9
E9
E9
E9
E912
11
25
24
13
26 1
1
1
1 2
2
2
2L
R
Y
W
BR
BR B±R
B±R
B±R
B±R B
B
BB J21
J/CB B±R B±R
W±R
B±G
B
B±RIG Switch Battery
Instrument
Panel J/B
Engine Room
J/B No. 2 FL
Block 1
1
AM2
2L 4
2A 11C8
1K3
1K5
1B 5
MAIN
FL
EC II3 12
W±R
F4
F6 6
7
*1: w/o Immobiliser
*2: w/ Immobiliser(*1) (*2)
E910
E99
(*1) (*2)
DI±90
± DIAGNOSTICSENGINE (5S±FE)
325 Author: Date:
WIRING DIAGRAM

± DIAGNOSTICSENGINE (5S±FE)
DI±91
326 Author: Date:
CONFIRMATION DRIVING PATTERN
(1) Connect the TOYOTA hand±held tester or OBD II scan tool.
(2) Record DTC and the freeze frame data.
(3) Use the TOYOTA hand±held tester to set to Check Mode. (See page DI±3)
(4) Drive the vehicle several times with the engine speed, load and its surrounding range shown with
ENGINE SPD, CALC LOAD in the freeze frame data or MISFIRE RPM, MISFIRE LOAD in the data list.
If you have no TOYOTA hand±held tester, turn the ignition switch OFF after the symptom is simulated
the first time. Then repeat the simulation process again.
HINT:
In order to memorize DTC of misfire, it is necessary to drive around MISFIRE RPM, MISFIRE LOAD in the
data list for the following period of time.
Engine SpeedTime
Idling3 minutes 30 seconds or more
1000 rpm3 minutes or more
2000 rpm1 minutes 30 seconds or more
3000 rpm1 minutes or more
(5) Check whether there is misfire or not by monitoring DTC and the freeze frame data. After that, record
them.
(6) Turn the ignition switch OFF and wait at least 5 seconds.

DI±92
± DIAGNOSTICSENGINE (5S±FE)
327 Author: Date:
INSPECTION PROCEDURE
HINT:

If is the case that DTC besides misfire is memorized simultaneously, first perform the troubleshooting
for them.

Read freeze frame data using TOYOTA hand±held tester or OBD II scan tool. Because freeze frame
data records the engine conditions when the malfunction is detected, when troubleshooting it is useful
for determining whether the vehicle was running or stopped, the engine warmed up or not, the air±fuel
ratio lean or rich, etc. at the time of the malfunction.

When the vehicle is brought to the workshop and the misfire is not occurred, misfire can be confirmed
by reproducing the condition or freeze frame data. Also, after finishing the repair, confirm that there
is no misfire. (See the confirmation driving pattern)

When either of SHORT FT #1, LONG FT #1, SHORT FT #2 or LONG FT #2 in the freeze frame data
is besides the range of ±20%, there is a possibility that the air±fuel ratio is inclining either to ºrichº
(±20% or less) or ºleanº (+20% or more).

When COOLANT TEMP in the freeze frame data is less than 80°C (176°F), there is a possibility or
misfire only during warming up.

In the case that misfire cannot be reproduced, the reason may be because of the driving with lack or
fuel, the use of improper fuel, a stain of ignition plug, and etc.
1 Check wire harness, connector and vacuum hose in engine room.
CHECK:
(a) Check the connection conditions of the wire harness and connector.
(b) Check the disconnection, piping and break of the vacuum hose.
NG Repair or replace, then confirm that there is no
misfire (See the confirmation driving pattern).
OK

A00434
± DIAGNOSTICSENGINE (5S±FE)
DI±93
328 Author: Date:
2 Check spark plug and spark of misfiring cylinder.
PREPARATION:
(a) Disconnect the high±tension cord from the spark plug.
(b) Remove the spark plug.
CHECK:
(a) Check the plug type.
(b) Check the electrode for carbon deposits.
(c) Check the electrode gap.
OK:
(a) Platinum±tipped spark plugs with twin ground
electrodes.
Recommended spark plug:
ND made: PK20TR11
NGK made: BKR6EKPB±11
(b) No large carbon deposit present.
Not wet with gasoline or oil.
(c) Electrode gap: 1.1 mm (0.043 in.)
PREPARATION:
(a) Install the spark plug to the high±tension code.
(b) Disconnect the injector connector.
(c) Ground the spark plug.
CHECK:
Check if spark occurs while the engine is being cracked.
NOTICE: To prevent excess fuel being injected from the in-
jectors during this test, don't crank the engine for more
than 5 ~ 10 seconds at a time.
OK:
Spark jumps across electrode gap.
NG Replace or check ignition system
(See page IG±1).
OK

A03015A03416
#10 (+) #20 (+) ON
#30 (+)
#40 (+) w/o Immobiliser
w/ Immobiliser
#10 (+)
#20 (+)#30 (+)
#40 (+)
FI6588
FI6538
A00064
Injector Signal Waveform
10 V/
Division
GND
100 msec./Division (Idling)GND
Injection duration1 msec./Division (Idling) 10 V/
Division(Magnification)
DI±94
± DIAGNOSTICSENGINE (5S±FE)
329 Author: Date:
3 Check voltage of ECM terminal for injector of failed cylinder.
PREPARATION:
(a) Remove the glove compartment (See page SF±64).
(b) Turn the ignition switch ON.
CHECK:
Measure voltage between applicable terminal of the ECM con-
nector and body ground.
OK:
Voltage: 9 ~ 14 V
Reference: INSPECTION USING OSCILLOSCOPE
INJECTOR SIGNAL WAVEFORM
With the engine idling, measure between terminals #10 ~ #40 and E01 of the ECM connector.
HINT:
The correct waveforms are shown.
OK Go to step 4.
NG

± DIAGNOSTICSENGINE (5S±FE)
DI±95
330 Author: Date:
4 Check resistance of injector of misfiring cylinder (See page SF±20).
NG Replace injector.
OK
Check for open and short in harness and
connector between injector and ECM
(See page IN±31).
5 Check fuel pressure (See page SF±6).
NG Check and repair fuel pump, pressure regula-
tor, fuel pipe line and filter.
OK
6 Check injector injection (See page SF±23).
NG Replace injector.
OK
7 Check EGR system (See page EC±12).
NG Repair EGR system.
OK

DI±96
± DIAGNOSTICSENGINE (5S±FE)
331 Author: Date:
8 Check manifold absolute pressure sensor and engine coolant temp. sensor
(See pages SF±53 AND SF±49).
NG Repair or replace.
OK
Check compression pressure, valve
clearance and valve timing
(See pages EM±3, EM±4 AND EM±23).

A03598
Knock Sensor 1ECM
KNK
E1 E8 13
W 1
*1: w/o Immobiliser
*2: w/ Immobiliser
(*1) (*2)
E812
± DIAGNOSTICSENGINE (5S±FE)
DI±97
332 Author: Date:
DTC P0325 Knock Sensor 1 Circuit Malfunction
CIRCUIT DESCRIPTION
The knock sensor is fitted to the cylinder block to detect engine knocking. This sensor contains a piezoelec-
tric element which generates a voltage when it becomes deformed, which occurs when the cylinder block
vibrates due to knocking. If engine knocking occurs, ignition timing is retarded to suppress it.

DTC No.DTC Detecting ConditionTrouble Area
P0325
No knock sensor 1 signal to ECM with engine speed, 1,200
rpm or more
(2 trip detection logic)
Open or short in knock sensor 1 circuit

Knock sensor 1 (looseness)

ECM
HINT:
If the ECM detects above diagnosis conditions, it operates the fail safe function in which the corrective retard
angle value is set to the maximum value.
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
Read freeze frame data using TOYOTA hand±held tester or OBD II scan tool. Because freeze frame records
the engine conditions when the malfunction is detected, when troubleshooting it is useful for determining
whether the vehicle was running or stopped, the engine warmed up or not, the air±fuel ratio lean or rich, etc.
at the time of the malfunction.
DI012±10

A03016A03417
LOCK
KNK E8 Connector
w/o Immobiliser
w/ Immobiliser
KNK
E8 Connector
DI±98
± DIAGNOSTICSENGINE (5S±FE)
333 Author: Date:
1 Check continuity between terminal KNK of ECM connector and body ground.
PREPARATION:
(a) Remove the glove compartment (See page SF±64).
(b) Disconnect the E8 connector from the ECM.
CHECK:
Measure resistance between terminal KNK of the ECM connec-
tor and body ground.
OK:
Resistance: 1 MW or higher
OK Go to step 3.
NG
2 Check knock sensor 1 (See page SF±57).
NG Replace knock sensor 1.
OK
3 Check for open and short in harness and connector between ECM and knock
sensor 1 (See page IN±31).
NG Repair or replace harness or connector.
OK