1998 NISSAN GT-R AUX

TROUBLE DIAGNOSES
Symptom Matrix Chart (Cont'd)
An open circuit causes no fuel injection to the corresponding cylinder, and the heated oxygen sensor output becomes lean. When the open circuits are
observed at all cylinders, the engine will not start.
Actuator-related malfunction
Injector Symptom
characteristics and inspection hints
Drive
circuit
lgnition signal
(POW&
transistor
drive
siqnal)
(open
Injection Open
Short
Fuel pump relay
1 Open 1 Engine will not start. In case of instantaneous break, surging may occur.
A
short circuit causes continuous fuel injection to the corresponding cylinder, and
over-rich airlfuel ratio and misfire will be noted. When the short circuits are
observed at all cylinders, the engine will not start.
Foreign
material
Clogs
L
Foreign
material causes continuous fuel injection to the corresponding cylinder.
Symptoms vary with the condition how the injection port is clogged.
Aidfuel ratio
compensation factor becomes larger.
(1 10 to 125%)
Canister purge control valve Ignition primary
signal (Power
transistor ground)
Auxiliary electric fan relay
[RB25DE, RB25DETI
1 Short
Open
Open -
Open
Open
Leaks
Open
Open
lgnition coil
AAC valve
The valve purges constantly. In summertime, engine may stall at idle speed due
i to rich aidfuel ratio. In wintertime, various malfunctions may occur due to lean
airlfuel ratio.
An open circuit causes no fuel injection to the corresponding cylinder, and the '
heated oxygen sensor output becomes lean. When the open circuits are observed at all cylinders, the engine will not start. In case of instantaneous 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.
The engine will stall when break time is long.
AAC valve is fully closed. Symptoms vary with the base engine speed. When it is
too low, engine may stall while the vehicle is decelerating or when the power
steering load or electrical load is applied.
Power
supply
s~de
primary
Second-
arY side
Power
supply
Drive
circuit
Open Open Auxiliary
electric fan will not operate even after warm-up is completed.
The valve
will not purge. Gasoline smell may be noted when the weather is hot.
Variable valve timing control
solenoid valve
Variable air intake control sole-
noid valve (NA)
Air jet swirl control solenoid
valve
[RB20DE
(UB)]
Injector ground (Total ground) lnstanta- Symptoms vary
with the break time and the vehicle's driving conditions. Surging neous break or engine stall may occur when the instantaneous break occurred during fuel
I I injection. I
Open
, Open
Short
Turbo pressure control solenoid
valve (TIC) Valve
timing not switched.
Variable air intake valve opens, and torque in low speed range is reduced.
Variable air intake valve closes, and torque in high speed range is reduced.
Open
Short Air jet
swirl control valve remains closed.
Air jet swirl control valve remains open.
Open
Open Swing valve opens earlier, and
maximum turbo pressure is reduced.
Engine will not start
because the injectors do not operate.

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.

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.

ENGINE MECHANICAL
TIGHTENING TORQUE
Engine cover
' Throttle body
Throttle position sensor
IAA unit (ACC valve)
' Intake 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
Ttming 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 Unit:
Nm (kg-m)
5.0
- 6.5 (0.51 - 0.66)
1) 8.8
- 11 (0.9 - 1.1)
2) 18
- 22 (1.8 - 2.2)
2.0
- 2.4 (0.20 - 0.24)
8.4
- 11 (0.86 - 1 .I)
18
- 22 (1.8 - 2.2)
5.1
- 6.5 (0.52 - 0.66)
20
- 29 (2.0 - 3.0)
1) 5.5 - 7.5 (0.56 - 0.76)
2) 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)
(M 1 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 center
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)
5) 95" - 100"
(Angle tightening)
E
9.0 - 12 (0.92 - 1.2)
25
- 34 (2.5 - 3.5) j$? 49 - 59 (5.0 - 6.0)
1) 14- 16
(1.4- 1.6)
2) 60"
- 65" BR
(Angle tightening)
93
- 103 (9.5 - 10.5)
34 - 44 (3.5 - 4.5)
25
- 34 (2.5 - 3.5) a=
': Tighten as specified tightening order.
1): Tighten separately in several times.

ENGINE MECHANICAL pEZBq
TIGHTENING TORQUE
Engine cover
' Throttle body
Throttle position sensor
IAA unit
(ACC valve)
' Intake manifold collector
* Intake manifold
Engine coolant temperature
sensor
' Fuel tube
Pressure regulator
Fuel damper
Fuel hose clamp bolt
(in engine compartment)
Turbocharger Oil tube
Water tube (block side)
(turbocharger side)
Oxygen sensor
Exhaust manifold cover
' Exhaust manifold
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 Unit:
N.m (kg-m)
5.0
- 6.5 (0.51 - 0.66)
1)
8.8
- 11 (0.9 - 1.1)
2)
18
- 22 (1 -8 - 2.2)
2.0
- 2.4 (0.20 - 0.24)
8.4
- 11 (0.86 - 1.1)
18
- 22 (1.8 - 2.2)
18
- 22 (1 -8 - 2.2)
20
- 29 (2.0 - 3.0)
5.1
- 6.5 (0.52 - 0.66)
20
- 29 (2.0 - 3.0)
1) 5.5
- 7.5 (0.56 - 0.76)
2) 5.5 - 7.5 (0.56 - 0.76)
(Tighten separately in twice.)
' Cylinder head boit
Cylinder head sub bolt
VTC solenoid
" Main bearing cap
Connecting rod
nut
Oil jet
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 center
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)
5) 95"
- 100"
(Angle tightening)
I%
9.0 - 12 (0.92 - 1.2)
25
- 34 (2.5 - 3.5)
49
- 59 (5.0 - 6.0) AT
1) 14 - 16 (1.4 - 1.6)
2) 60" - 65"
(Angle tightening) BR
30 - 40 (3.1 - 4.1)
93
- 103 (9.5 - 10.5)
34 - 44 (3.5 - 4.5) ST
25 - 34 (2.5 - 3.5)
3.8
- 4.5 (0.39 - 0.46) I%$
5.1 - 6.5 (0.52 - 0.66)
17
- 21 (1.7 - 2.1)
20
- 23 (2.0 - 2.3) kIA
35 - 47 (3.6 - 4.8)
16
- 21 (1.6 - 2.1)
9.0
- 12 (0.92 - 1.2) a=
': Tighten as specified tightening order.
1): Tighten separately in several times.