1995 TOYOTA SUPRA fuel pressure

DTC 35 Turbo Pressure Sensor Circuit Barometric Pressure (BARO)
Sensor Circuit
CIRCUIT DESCRIPTION
HINT DTC 35 is used to indicate malfunctions in the turbo pressure sensor circuit or BARO sensor circuit.
1. TURBO PRESSURE SENSOR
This sensor detects the air intake chamber pressure and converts the pressure reading into a voltage which
is used to control the turbo pressure by the ECM.
If the ECM detects the below diagnosis conditions, it operates the fail safe function in which the ECM stops
fuel injection at engine speed 2,400 rpm or more and throttle opening angle 20° or more.
 
 DTC No. 
 Circuit 
 Diagnostic Trouble Code Detecting Condition 
 Trouble Area
 
 
 
 
35
 
 
 
 
Turbo
Pressure
Sensor 
 
 
 
Open or short in turbo pressure sensor
circuit for 0.5 sec. or more
 
 
 
 

Open or short in turbo
pressure sensor circuit

Turbo pressure sensor

ECM
2. BARO SENSOR
This sensor is built into the ECM. It is used to detect the atmospheric (absolute) pressure and outputs corre-
sponding electrical signals. Fluctuations in the air pressure cause changes in the intake air density which
can cause deviations in the air±fuel ratio. The signals from BARO sensor are used to make corrections for
the fluctuations. If the ECM detects the below diagnosis conditions, it operates the fail safe function in which
the atmospheric pressure is assumed to be 101.3 kPa (1.03 kgf/cm
2, 14.7 psi).
 DTC No. Circuit Diagnostic Trouble Code Detecting Condition Trouble Area 
 
 
 
 
 
35
 
 
 
 
 
 
BARO
Sensor
 
 
 
 
 
 
Open or short in BARO sensor circuit for
0.5 sec. or more
 
 
 
 
 
 

ECM
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTINGEG±549

See page EG±503.
CIRCUIT DESCRIPTION
The EGR system is designed to recirculate the exhaust gas, controlled according to the driving condi-
tions back into the intake air±fuel mixture. It helps to slow down combustion in the cylinder and thus
lower the combustion temperature which, in turn, reduces the amount of NO
x emission. The amount
of EGR is regulated by the EGR vacuum modulator according to the engine load.
If even one of the following conditions is fulfilled,
the VSV is turned ON by a signal from the ECM.
This resists in atmospheric air acting on the EGR
valve, closing the EGR valve and shutting off the
exhaust gas (EGR cut±OFF).

Engine coolant temp. below 50°C (122°F)

During deceleration (throttle valve closed)

Light engine load (amount of intake air very
small)

Engine speed over 4,800 rpm

Manifold absolute pressure more than 120 kPa
(1.2 kgf/cm
2, 17.4 psi)
DTC No.Diagnostic Trouble Code Detecting ConditionTrouble Area
No No.1 knock sensor signal to ECM for 4
crank revolutions with engine speed between
2,050 rpm and 5,950 rpm

Open EGR gas temp. sensor circuit

Short in VSV circuit for EGR

EGR hose disconnected, valve stuck

Clogged EGR gas passage

ECM
EGR gas temp. and intake air temp. are
60°C(140°F) or less for A/T, 55°C (131°F) or
less for M/T for 1 ~ 4 min. under conditions (a)
and (b):
(2 trip detection logic)*
(a) Engine coolant temp.: 60°C (140°F) or
more
(b) EGR operation possible (Example A/T in
3rd speed (5th for M/T), A/C ON, 96 km/h
(60 mph), Flat road)
Purpose of the driving pattern.
(a) To simulate diagnostic trouble code detecting condition after diagnostic trouble code is recorded.
(b) To check that the malfunction is corrected when the repair is completed by confirming that diagnos±
tic trouble code is no longer detected.
DIAGNOSTIC TROUBLE CODE DETECTION DRIVING PATTERN
DTC 71 EGR System Malfunction
EG±564± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

(See page IN±30).
Check for ECM power source circuit (See page
EG±576), and check for open in harness and
connector between terminal +B of data link
connector 1 and main relay.
(1) Turn ignition switch ON.
(2) Using SST, connect terminals +B and FP of data
link connector 1.
SST 09843±18020
Check that there is pressure in the hose from the fuel
filter.
Fuel pressure can be felt.
Check fuel pump operation.
Repair or replace harness or connector.
Check for open and short in harness and connector between terminals
+B
+B, FP
FP of the data link connector 1 and fuel pump ECU (See
page IN±30).
Turn ignition switch ON.
Measure voltage between terminal +B of data link con-
nector 1 and body ground.
Voltage: 9 Ð 14 V
Check voltage of terminal +B of data link connector 1.
Check for ECM power source circuit (See
page EG±576), and check for open in harness
and connector between terminal +B of data
link connector 1 and main relay.
INSPECTION PROCEDURE
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTINGEG±569

VSV Circuit for Fuel Pressure Control
CIRCUIT DESCRIPTION
The ECM turns on a VSV (Vacuum Switching
Valve) to draw air into the diaphragm chamber
of the pressure regulator if it detects that the
temperature of the engine coolant is too high
during engine starting.
The air drawn into the chamber increases the
fuel pressure to prevent fuel vapor lock at high
engine temperature in order to help the en-
gine start when it is warm.
Fuel pressure control ends approx. 120 sec.
after the engine is started.
± ENGINE2JZ±GTE ENGINE TROUBLESHOOTINGEG±595

INSPECTION PROCEDURE
(1) Remove VSV.
(2) Disconnect VSV connector.
(1) Measure resistance between terminals.
(2) Measure resistance between each terminal
and the body.
(1) Resistance: 33 Ð   at 20°C (68°F)
(2) Resistance: 1 M or higher
Check operation of VSV when battery positive volt-
age is applied and released to the VSV terminals.
Battery positive voltage is applied:
Air from port E is flowing out through the air fil-
ter.
Battery positive voltage is not applied:
Air from port E is flowing out through port G.
Check VSV for fuel pressure control.
Replace VSV for fuel pressure control.
EG±596± ENGINE2JZ±GTE ENGINE TROUBLESHOOTING

TROUBLESHOOTING
HINT: Before troubleshooting the turbocharger, first check the engine itself. (Valve clearance, engine com-
pression, ignition timing etc.)
Check intake air system, and repair or replace parts
as necessary. (See page
EG±144)
1. TURBOCHARGING PRESSURE TOO
LOW
2. RESTRICTED INTAKE SYSTEM
6. ERRATIC TURBOCHARGER
OPERATION
3. LEAK IN INTAKE AIR SYSTEM
4. RESTRICTED EXHAUST SYSTEM
5. LEAK IN EXHAUST SYSTEM
INSUFFICIENT ACCELERATION, LACK OF POWER OR EXCESSIVE FUEL
CONSUMPTION
(Possible Cause) Check Procedure and Correction Method)
Check turbocharging pressure. (See page EG±144)
Turbocharging pressure:
61±75 kPa
(062±0.76 kgf/cm
2,
8.8±10.8 psi)
If the pressure is below specifications, begin
diagnosis from item 2.
Check intake air system, and repair or replace parts
as necessary. (See page
EG±144)
Check intake air system, and repair or replace parts
as necessary. (See page
EG±144)
Check intake air system, and repair or replace parts
as necessary. (See page
EG±144)
Check rotation of turbine shaft. If it does not
turn or turns with a heavy drag, replace the
turbocharger assembly.
Check axial and radial play of turbine shaft.
(See page EG±158)
Maximum axial play : 0.110 mm (0.0045 in.)
Maximum radial play : 0.162 mm (0.0064 in.)
If the play is greater than maximum, replace
the turbocharger assembly. EG±142
± ENGINETURBOCHARGER SYSTEM (2JZ±GTE)