engine coolant NISSAN GT-R 1998 User Guide

TROUBLE DIAGNOSES
CONSULT (Cont'd)
DATA MONITOR MODE
ECM input
signals
Monitored item
[Unit] Main
signals Remarks
Description
lndicates the engine speed computed
from the POS signal (lo signal) of the
camshaft position sensor.
When the engine is stopped, a certain
value is indicated.
When the engine coolant temperature
sensor is open or short-circuited, ECM
enters fail-safe mode. The engine coolant
temperature determined by the ECM is
displayed.
The signai voltage of the mass air flow
0 sensor is displayed.
The engine coolant temperature (deter-
mined by the signal voltage of the engine
0 coolant temperature sensor) is displayed.
-
MAS AIRiFL SE [V]
The signal voltage of the oxygen sensor
is displayed.
02
SEN [V]'
0 After turning ON the ignition switch, "RICH" is displayed until air-fuel mixture
ratio feedback control begins.
When the air-fuel ratio feedback is
clamped, the value just before the clamp-
ing is displayed continuously.
MiR
F/C MNT*
[RICH/LEAN] Display of oxygen sensor signal during
air-fuel ratio feedback control:
RICH
... means the mixture became
"rich", and control is being affected
toward a leaner mixture.
LEAN
... means the mixture became
"lean", and control is being affected
toward
a rich mixture.
The vehicle speed computed from the
vehicle speed sensor signal is displayed. VHCL SPEED SE [krn/h] or [mph]
The power supply voltage of ECM is dis-
played. I BATTERY VOLT [V]
THRTL POS SEN [V] The throttle position sensor signal volt-
age is displayed.
Throttle motor sensor output voltage Approx. 4.6V THRTL POS SE2 [V] 0 RB25DET
TURBO BOOST
SENSOR
RB25DET
Turbo pressure sensor output voltage 0 Approx. 2.7V
Indicates [ON/OFF] condition from the After starting the engine, [OFF] is dis-
0 starter signal. played regardless of the starter signal.
lndicates [ON/OFF] condition from the 0 throttle position sensor signal.
-
START SIGNAL
[ON/OFF]
CLSD THUP SW
[0
N/O
FF]
0 lndicates [ON/OFF] condition of the air
conditioner switch as determined by the
air conditioner sianal. AIR COND SIG
[ON/OFF]
lndicates [ON/OFFj condition from the
parldneutral position switch signal.
PiN
POSl SW [ONIOFF)
PW/ST SIGNAL
[ONIOFF]
LOAD SIGNAL
[ON/OFF]
lndicates [ON/OFfl condition from the
electrical load signal
andlor lighting
switch.
ON ... rear defogger is operating.
OFF ... rear defogger is not operating.
NOTE: Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically. *: Models with three way catalyst.

TROUBLE DIAGNOSES
CONSULT (Cont'd)
ACTIVE TEST MODE
INJECTION I . CCohArthe amount of fuel injection
TEST ITEM
CONDITION
Engine: Return
to the original trouble
- I . Engine: After warming up, idle the
IACV-AACN
OPENING
ENG COOLANT
TEMP
IGNITION TIMING
US~~~CONSULT.
Engine: After warming up, idle the
engine.
Change the IACV-AAC valve opening
percent using CONSULT.
Engine: Return to the original trouble
conditioo
Change the engine coolant
temperature using CONSULT.
Engine: Return to the original trouble
condition
Timing light: Set Retard the ignition timing using CONSULT.
POWER BALANCE engine. A/C switch "OFF . Shift lever uNn
COOLING
FAN RB25DE, RB25DET
FUEL PUMP RELAY
VlAS SOL VALVE RB20DE (UB), RB25DE
JUDGEMENT
Cut off each injector signal one at a
time using CONSULT.
Ignition switch: ON Turn the cooling fan "ON" and "OFF
using CONSULT.
0 lgnition switch: ON (Engine stopped) . Turn the fuel pump relay "ON" and
"OFF using CONSULT and listen to
operating sound. CHECK
ITEM (REMEDY)
If trouble symptom disappears, see
CHECK ITEM. : ~,"~~,,,~scOnnectOr Oxygen sensor
Engine speed changes according to the
opening percent.
. Harness and connector IACV-AAC valve
If trouble
symp:orn disappears, see
CHECK ITEM. : Sensor 0 Fuel injectors
If trouble symptom disappears, see
CHECK ITEM. 0 Adjust ignition timing (by moving
camshaft position sensor)
Engine runs rough or dies.
Harness and connector Compression Injectors 0 lgnition coil with power transistor Spark plugs
Cooling fan moves and stops.
Hamess and connector Cooling fan motor Cooling fan relay
Fuel pump relay makes the operating
sound.
. Harness and connector Fuel pump relay
VALVE
TIMING
SOL
SWIRL CONT SOL
VALVE
0 RB20DE (UB)
SELF-LEARNING
CONT
PURG VOL CONTN
Checks control items and output circuit by arbitrary ON/OFF operation.
. In this test, the coefficient of self-learning control mixture ratio returns to the original coefficient by touching "CLEAR" on the
screen.
. Harness and connector EVAP canister purge control solenoid
valve
Vacuum hose
0 Engine: Run engine at 2,000 rpm. . Turn the EV~P canister purge control solenoid valve and using CONSULT and listen for operating
sound. EVAP
canister purge control solenoid
valve makes an operating sound. Check
vacuum signal for EVAP canister purge ~~~~~~a'cuum exists. VC OFF ... Vacuum does not exist.

TROUBLE DIAGNOSES
Symptom Matrix Chart
RELATION BETWEEN CONTROL ITEMS AND SENSORSfACTUATORS
@: High possibility to control damage 0: Low possibility to control damage
Sensors and actuators
1$1$1$ r I I
Crankshaft position sensor 1@1@1@
Ring gear crankshaft position sensor
[RB20DE (UB)] @
Mass air flow sensor
I Engine coolant temperature sensor I 0 I @ I 0 i I
Heated oxygen sensor 0
Knock sensor
Vehicle speed sensor
e? - 01 0
Throttle position sensor 000 C. $ Turbo pressure sensor (TIC) 0 0
Refrigerant pressure sensor
START
lgnition switch
@ 0
IGN 000
Air conditioner switch
Parklneutral position switch
Power steering oil pressure switch
Electrical load switch
Battery
voltage
0
injector @GO I
I power transistor I I I Ignition system I I I lgnition coil I I I I
AAC valve
Fuel DumD relav
. . I I I
2 o ECM & IGN coil relay I@l@l@ 1 I I % Auxiliary electric fan relay 3 - 2 Air conditioner relay
Canister purge control valve
0
Variable valve timing control solenoid valve
Variable air intake control solenoid valve
, (NA) Air jet swirl control solenoid valve
[RB20DE (UB)] 0
Turbo pressure control solenoid valve
(TW
FPCM (TIC)
%' Dropping resistor (TIC) 2. I I 5 Air regulator
Canister 0

TROUBLE DIAGNOSES
Symptom Matrix Chart (Cont'd)
-RELATION BETWEEN TROUBLE SYMPTOMS AND SENSORS
-. - Sensors No I Hard
start start Rough
idle
Poor derivability Engine
stall
Symptom
@: High possibility 0: Low possibility
Crankshaft position
sensor (POS,
REF) Instantaneous
xeak
Ring gear crankshaft
position sensor
[RB20DE
(UB)]
s 1 Signal iigh output
,ow output
"
2 Power supply
Engine coolant tem-
perature sensor
iigh resistance
-ow resistance
- -- Heated oxygen sen-
sor
Knock sensor
iigh output
.ow output
Ipedshort
Vehicle s~eed sensor
Throttle position sen-
sor Jnstable output
'oar adjustment
Turbo pressure sen-
sor
(TIC)
Refrigerant pressure
sensor
Ignition switch (IGN)
k$n;pRnT)sw
i tch
Air conditioner switch
ParWneutral position
switch
Power steering oil
pressure switch
Electrical load switch
Multiplex communica-
tion line
Control unit power
supply
Sensor ground
Control unif and con-
nector
*: Fast idle
'oor contact
Vater intrusion

TROUBLE DIAGNOSES
Symptom Matrix Chart (Cont'd)
Sensor-related problems I Symptom characteristics and ins~ection hints
Open Engine
will not start when either REF signal circuit or POS signal circuit is open.
Neither fuel system nor ignition system outputs control signals.
Crankshaft position sensor
(POS, REF) Instanta-
neous break Symptoms
vary with the break time and the vehicle's driving conditions. Light
shock or surging will occur while the vehicle is being driven, and the engine will
stall at idle speed.
Ring gear crankshaft position
sensor
[RB20DE
(UB)]
Signal
Mass air flow sensor Open
Open
High output
Low output I Aidfuel
ratio becomes lean. Dirty hot wire or air entering the system could be the
cause. No
airfluel ratio compensation
is carried out during lean bum status. Drivability
may be affected.
Enters fail-safe mode. Driving under
2,400 rpm is allowed.
Airlfuel
ratio becomes rich. Black smoke may be noted. Poor contact at the
ground could be the cause.
Engine coolant temperature sen-
sor Open
Open
Opedshort
High resis-
tance
Low resis-
tance
Opedshort
Heated oxygen sensor
I
Airlfuel ratio becomes over-rich.
Same symptom as when signal wire is open.
Enters fail-safe mode. Malfunction indicator lamp comes ON. Ordinary driving is
allowed. Problems tend to occur when engine is cold or engine coolant tempera-
ture
is high.
Detects low engine coolant temperature. Problems tend to occur after engine
warm-up.
Detects high engine coolant temperature. Problems tend to occur when engine is
cold.
Base
aidfuel ratio is used.
lgnition timing is retarded within the knock control range. Lack of power may be
OpedShort
I noted.
Knock sensor lgnition
timing is retarded within the knock control range. Lack of power may be
High
Output
(noted.
Low output
1 lgnition timing may not be retarded when knock is detected.
Vehicle speed sensor
Throttle position sensor
Opedshort
Opedshort
Unstable out-
put
Poor adjust-
ment
Open
Turbo pressure sensor
(TE) Fuel
cut time becomes-shorter, or no fuel cut is observed.
Base idle speed is used. Fuel injection is not increased during acceleration.
AIT shift point changes for AfF vehicles.
Unnecessary cut-in fuel injection could be the cause. Poor contact at the ground
or control unit could be the cause.
ldle judgment is "OFF while idling. Condition returns
normal by turning the igni-
tion switch ON and OFF repeatedly.
Turbo pressure is judged zero. No remarkable malfunction will be detected.
Refrigerant pressure is judged high. ldle speed remains high while the air condi-
tioner is ON.
Refrigerant pressure sensor
Short Refrigerant pressure
is judged low. ldle speed remains low while the air condi-
tioner is ON.
lgnition switch (IGN)
lgnition switch (START)
Air conditioner switch Open
Engine
will not start because neither fuel system nor ignition system outputs con-
trol signals.
Engine starts in normal condition. Engine may not start when temperature is
extremefy
low.
Air conditioner will not operate. No other malfunction will be noted.
Park/neutral
position switch is judged "OFF. Target engine speed for cold engine
in
N or P position is reduced.
ParWneutral position switch is judged
"0N"I Fast Jdle is effective when the engine
is cold and the gear is in other than N and P posrtlons. Vehrcle excessrvely
creeps.
Open
Open
Parklneutral
position
switch
Short
Power steering oil pressure
switch Open
Engine may
stall when the steering wheel is turned while the vehicle is standstill
and the accelerator pedal is lightly pressed, or when the steering wheel is turned
Electrical load switch Short
Open
Open/short
Multiplex communication line
- -- during deceleration. '
Power steering switch is judged 'ON." Value will be compensated constantly.
Idle speed drops so that the engine can stall when electrical load is applied.
Torque reduction control is not performed. Therefore,
shift shock becomes
greater.
- -- -- -- -- Engine will not start because neither fuel system nor ignition system outputs con-
trol signals.
Open
Control unit power supply
- -- - - --- - - - - - O~edshort I Same symptoms as when sensor harness is open.
Sensor ground -- - Poor contact
Water intru-
sion - -- - - - - - -- -- In case of poor contact, the connector fitting may be loose. In case of water
intrusion, the engine stalls and become inoperative for a while. The engine may restart soon in some cases.
Control unit
and connector

TROUBLE DIAGNOS
ECM (.TCM) lnpu
:s
3utput Signal Reference
Value (Cont'd)
.. No.
Fluctuates between approx. 0.1 to
0.4V and approx.
0.7 to
0.9V At
idle
- I I - I I -
I
I
- are measured
At approx. 2,000 rpm
:v: i .5 I .O 0.5 0
ECL 1 8645 11jllllllll ECL 1 8630
Throttle motor sensor
signal
[RB25DET'J Approx. 3.4V
I (Voltage becomes lower when TCS operates.)
Motor throttle switch
signal
[RB25DET]
Approx.
4.7V
Mass air flow sensor
signal
t
(When TCS is operating: Approx. OV)
Ignition switch ON: Approx.
0.2V
At idle: Approx.
1
.I - 1.2V Approx.
1.6 - 1.7V
Mass air flow sensor
ground Approx.
OV
I
Coolant temperature approx. 20°C: Approx. 3.5V
Coolant temperature approx.
80°C: Approx. 1.2V
Approx. 0.36V min.
(Voltage increases as the air conditioner refrigerant
pressure increases.)
Approx. 0.4
- 2V (') ': Voltage varies with measuring range (internal resis-
tame) of a circuit tester.
Battery voltage
C
+
+
+
56
-
62 1 Knock sensor signal 1
Engine coolant tem-
perature sensor signal
57
- -- -
63 1 Knock sensor signal 2
Refrigerant pressure
sensor
67 Control unit power
sup-
72
I PIY Receive (Data input to
control unit) 1
Transmit (Data output
from control unit) CONSULT
connected: Approx. 0.25V
CONSULT
not connected: Battery voltage
CONSULT connected: Approx.
9V max. CONSULT not connected: Approx. OV
C
Fan stopped: Battery voltage
Fan operating: Approx. 0.2 - 0.3V 78
NOTE: Above
Auxiliary electric fan
relay control signal
[RB25DE, RB25Dm
voltages values obtained
analog circuit
tester.

TROUBLE DIAGNOSES
ECM (-TCM) Input/Output Signal Reference
Terminal No.
108
- NOTE:
Signal name
CM.TCM, TCS/ABS
tegrated control signal
dultiplex communica-
&DE.m,
B25DETj
attery power supply
ijector drive signal
3attery voltage When cranking: Approx.
10.5V
Value (Cont'd)
(v) 50 40 30 20 10
0
At idle: &Wry voltage
A:
idle
Approx. 2V
rariable
air intake con-
:ol solenoid valve con- switch ON: Battery voltage (Solenoid valve
rot signal
RB20DE (UB), At idle: Approx. 0.2
- 0.3V (Solenoid valve ON) At
approx. 2,000
rpm
t
3B25DEI ' .
-urbo pressure control iO1enOid valve Battery voltage (Solenoid valve OFF)
iianal
4ir jet swirl sole- Coolant temperature below approx. 70°C: Approx.
0.9V (Solenoid valve ON)
'Oid Coolant temperature approx. 70°C and above: Battery
RB20DE (VB)] voltage (Solenold valve OFF)
[RB20DE (UB), RB25DEl
Air conditioner OFF: Battery voltage
Air conditioner ON: Battery voltage Approx.
10V
(After approx.
15 sec.)
Zanister
purge control
~alve
control signal
M 30 20 10 0
(Waveform indicates when air conditioner is
ON.)
[RB20DETJ
Air conditioner OFF: Battery voltage
Air conditioner ON: Battery voltage
4 Approx. 1OV
(After approx. 15 sec.) Slightly lower than battery voltage
t At
approx. 3,650 rpm and above [RB2ODE (UB)]
At approx. 3,500 rpm and above [RB25Dq : Battery voltage (Solenotd valve OFF)
t [When engine raced suddenly: Approx. 0.3V (Solenoid
valve ON)]
t Coolant temperature approx. 70°C and above, and
driving at approx. 3,300 rpm and above [MTT] Coolant temperature approx. 70°C and above, and
driving at approx. 3,000 rpm and above [A/T1 : Approx. 0.9V (Solenoid valve ON)
Approx.
9V
Approx. 9V
I (Waveform indicates when air conditioner is ON.)
tester.

FULLY AUTOMATIC AIR CONDITIONER
Symptom
Trouble Diagnosis for Each Symptom
No airflow
Airflow does not change. Operation check
Check blower fan motor operation. (Refer to "Blower Fan Motor Sys-
tem Check".)
The above is normal.
I Automatic amolifier 1 Faultv automatic amplifier
Faulty attachment of air mix door
rod, or air mix door lever
Faulty air mix door system
ElG
(damage, lock, etc.)
Malfunctioning unit
Blower fan motor Probable cause
Faulty blower fan motor
Check attachment status of the air
mix door actuator.
Common item (Check and confirm this
item along with the fol-
lowing three items.)
Air mix door
Abnormal display in self-diagnosis
step
3
Check that the air mix door oper-
ates when the temperature
adjust-
ment dial is set to
18OC or 32°C.
Faulty sensor (Refer to 'Component a
Parts Inspection".)
Faulty sensor harness
Air
mix door actuator
Air mix door actuator
Abnormal display in self-diagnosis
step 2
Magnet clutch does not operate
Magnet clutch Refer
to 'Magnet Clutch System R8
with AUTO switch, or A/C switch. Check".
I Faulty
air mix door actuator
Faulty air mix door actuator system AT
hamess
(Refer to "Actuator System Check".)
BW
Refer to "Actuator System Check".
@'i?
Sensor
Tem- perature
control mal-
function No
cool airflow
(Flow amount is normal.)
ngeranr
cnarge
amounr.
( Cooler cycle 2 ~erformance. I Refer to 'Performance Test". I
The above is normal. I Automatic amolifier 1 Faulty automatic amplifier I
After warming up, the heater core
inlet and outlet hoses are not warm. 1 Coolant I
Engine coolant failure
Clogged heater hose or heater core
No warm airflow
(Flow
amount is normal.)
The above is normal. Automatic amplifier
1 Faulty automatic amplifier
Blower fan motor speed does not
change even when the fan switch is Blower fan motor
changed. Refer
to "Blower Fan Motor System
Check".
I
When the fan switch is in 4th, Faulty aspirator
smoke is not drawn in from the
in-
Aspirator Clogged
or disconnected aspirator
vehicle sensor inlet. duct
Large
in-vehicle tem-
perature difference in
relation to temperature
setting Check the setting difference
between the set temperature and
control temperature. Error
in temperature difference set-
ting
- The above isnormal.- Automatic amplifier Faulty automatic amplifier
Faulty attachment of mode door
lock, mode door link, or mode door
Check mode door operation. Mode door lever
Faulty mode door system (damage,
lock, etc.)
Faulty mode door actuator
Abnormal display in self-diagnosis Faulty mode door actuator system
step
3 Mode door actuator
harness (Refer to "Actuator System
Check".)
Air
outlet does not switch.
Normal display in self-diagnosis
Mode door actuator
step
3
Refer to "DOOR ACTUATOR
HARNESS", "Actuator System
Check".
The above is normal.
I Automatic amplifier I Faulty automatic amplifier - - I I Faulty attachment of intake door
Check intake door operation. lntake
door lever
Faulty intake door system (damage,
lock, etc.)
~aulG intake door actuator
Faulty intake door actuator system
hamess (Refer to "Actuator System
Check".)
Abnormal
display in self-diagnosis
door step 3 Air inlet does fiot switch.
Normal display in self-diagnosis
lntake door actuator
step
3
Refer to "DOOR ACTUATOR
HARNESS", "Actuator System
Check".
I I The above is normal. I Automatic amplifier I Faulty automatic amplifier

ENGINE MECHANICAL I RB~ODE (UB) ]
STANDARD AND REPAIR LIMIT
Firing order I 1-5-3-6-2-4
Compression pressure
MPa
(kg/cm2)/rpm
Distortion limit mm
- - -- --- - Ignition advance device
Electronically-controlled ignition advance
Engine
oil capacity
e
Spark plug standard
Limit
. Limit
of variation between cylinders
Intake manifold
Intake manifold collector
Exhaust manifold
Cylinder head
Cvlinder block
lgnition timing (during no feed back control) 1.23
(1 2%)/300
0.93 (9.5)1300
0.1 (1.0)/300
0.1 0.1
0.3
0.2
0.1
Without filter
With filter
MakerlTypeISpark
plug gap mm
Engine idling speed
W'
Idle base speed (during no feed back control)
rPm
Density of
COIHC at idling speed
Wppm Approx.
3.8
Approx. 4.2
NG WPFR5G-11 11.0
- 1
-1
650-.50
(N or P position for
A/T)
600 (N or P position for AlT)
Less than O.l/Less than 50
I New I Used I Limit
Valve
clearance
(INTIEXH)
mm
Deflection
amount of accessory V-belt
Measured with tension gauge
N (kg) Hot
engine
.
Cold engine (at ambient temperature)
Measured by pushing at 98 N (10 kg)
mm 0.36+0.062/0.53+0.062
0.31 1~,0.04/0.50i0.04
Fuel tank capacity
e
Engine coolant total capacity [with reservoir tank (max. level)] e
Thermostat opening temperature [start to open - full open]
"C
Radiator cap opening pressure
MPa (kg/cm2) Approx.
65
Approx. 9.4 82 - 95
0.06
- 0.1 0 (0.6 - 1 .O)
A/C compressor belt
Power
steering pump belt
Fan belt
Power steering pump belt
1 8-10 1 10-12 1 16
667
- 755
(68
- 77)
A/C compressor belt 1 6-8 1 7-9 / 12
Fan belt
1 3-5 1 4-6 1 7.5
559 - 637
(57
- 65)
SEC.117 Power steering
Fan belt pump be1 t
284 (29)

ENGINE MECHANICAL [ RB20DE (UB) 1
TIGHTENING TORQUE
Unit: N.m (kg-m)
Engine cover
Throttle body
Throttle position sensor
IAA unit (ACC valve)
lntake manifold collector
(upper)
Intake manifold collector
Intake manifold
Vacuum tank
Engine coolant temperature
sensor
- --
' Fuel tube
Pressure regulator
Fuel damper
Fuel hose clamp bolt
(in engine compartment)
Exhaust manifold cover
' Exhaust manifold
Oxygen sensor
Crank pulley
Cam pulley (INT)
Cam pulley
(EXH)
Timing belt cover
Timing belt rear cover
Tensioner pulley
Idler pulley
Crankshaft position sensor
' Oil pan
Oil strainer
Oil pan drain plug
ignition coil
Spark plug
* Rocker cover
Camshaft bracket
Camshaft baffle plate 5.1
- 6.5 (0.52 - 0.66)
20
- 29 (2.0 - 3.0)
1) 5.5 - 7.5 (0.56 - 0.76)
?) 5.5 - 7.5 (0.56 - 0.76)
:Tighten separately in twice.)
Cylinder head bolt
Cylinder head sub bolt
VTC solenoid
' Main bearing cap
Connecting rod nut
Flywheel and drive plate
Engine coolant drain plug
Knock sensor
Radiator mounting bracket
Auxiliary electric fan
Water pump (M6 bolt)
(M8 bolt)
(MI 0 bolt)
Water inlet
Oil pump assembly
Accelerator cable
lock nut
Fuel tank strap
Fuel sender unit lock
ring
Exhaust manifold to front
tube Front tube to catalytic
converter Catalytic converter to cent
tube Center tube to main
muffler
Alternator (main)
(stay side)
Starter motor Unit:
N-m (kg-m)
1)
29 (3.0)
2) 98 (10.0)
3)
0
(0)
4) 25
- 34 (2.5 - 3.5) GI
5) 95" - 100"
(Angle tightening)
Ec
9.0 - 12 (0.92 - 1.2)
25
- 34 (2.5 - 3.5)
49
- 59 (5.0 - 6.0) h$7'
1) 14 - 16 (1.4 - 1.6)
2) 45"
- 50"
(Angle tightening)
BW
93 - 103 (9.5 - 10.5)
34 - 44 (3.5 - 4.5)
25
- 34 (2.5 - 3.5) ST
': Tighten as specified tightening order.
1): Tighten separately in several times.