fuel pressure TOYOTA CAMRY 1999 Service Repair Manual

EVAP SYSTEM OPERATION INFORMATION ± EG005-01 April 27, 2001
Page 5 of 14
Late Type (Intrusive EVAP System) (Except ECHO)
Onboard Recovery Valve
(Fill Check Valve)Vapor
Pressure
SensorVacuum
Check
ValveTank Valve
AssemblyTank
Pressure
Valve
Canister
To
Manifold
Vacuum
Purge
VSV
Filtered
Air
Air Drain Valve
Air Valve AssemblyAir Inlet ValveCanister
Closed Valve
Bypass
VSVAir
Inlet LineService
Port
Tank Side
The bypass VSV and the fill check valve
assembly isolates the tank pressure side
from the canister side (see Figure 1).
Canister Side
The bypass VSV and the Fill Check valve
also isolate the canister side from the
tank side (see Figure 2).
Late Type
System
Description
(Continued)
Except ECHO
Figure 1. Fuel Tank Side of System
Except ECHO
Figure 2. Canister Side of System

EVAP SYSTEM OPERATION INFORMATION ± EG005-01 April 27, 2001
Page 7 of 14
ECHO Monitor Sequence
CCV Open
Purge
ClosedOpenClosed
Purge ClosedOpen Open
Cold Start ECT/IAT
Near Same TempNegative
Pressure
(Vacuum)
OccursTank &
Canister
Leak CheckCCV
Testing Vapor
Pressure
Sensor
Signal
Monitor Operation
The monitor sequence begins with a cold
engine start. The IAT and ECT sensors
must have approximately the same
temperature reading.
The ECM is constantly monitoring fuel
tank pressure. As the temperature of the
fuel increases, pressure slowly rises.
The ECM will purge the charcoal canister
at the appropriate time (see Figure 1).
With bypass VSV closed, pressure will
continue to rise in fuel tank.
Late Type
System
Monitor
Sequence
(Continued)
Except ECHO
Figure 1. Canister Purge
ECHO
Figure 1. Canister Purge

EVAP SYSTEM OPERATION INFORMATION ± EG005-01 April 27, 2001
Page 9 of 14
Vent Control, CCV Operation P0446
This stage checks the CCV and vent (air
inlet side) operation. When the vapor
pressure rises to a specified point, the
ECM opens the CCV. Pressure will
increase rapidly because of the air
allowed into the system. No increase or
an increase below specified rate of
pressure increase indicates a restriction
on the air inlet side (see Figure 4).
Bypass VSV Operation P0446
In the next stage, the ECM closes the
bypass VSV. This action blocks air
entering the tank side of the system. The
pressure rise on the fuel tank side is no
longer as great. If there was no change in
pressure, the ECM will conclude the
bypass VSV did not close (see Figure 5).Late Type
System
Monitor
Sequence
(Continued)Except ECHO
Figure 4. CCV Opens
ECHO
Figure 4. CCV Opens
Except ECHO
Figure 5. Bypass VSV Closes

EVAP SYSTEM OPERATION INFORMATION ± EG005-01 April 27, 2001
Page 11 of 14
Diagnostic Process Flow Chart
(Continued on following page)
PRELIMINARY CHECK
Fuel level should be between
1/4 and 3/4
Visually inspect for presence
of Fuel/Gas Cap
DO NOT TIGHTEN OR REMOVE!
PRESSURIZE EVAP SYSTEM (System Integrity Check)
This test checks for leaks in the canister and fuel tank sides. The CCV and Air Inlet Lines will be checked
separately.
A) Clamp the air drain hose on the charcoal canister with the supplied hose pliers from the EVAP System
Pressure Test Kit.
B) Locate the vapor pressure sensor. If the vapor pressure sensor has two hoses connected to it,
disconnect the hose between the air drain hose fitting at the vapor pressure sensor and plug the hose.
C) Connect the pressure supply hose from the Pressure Test Kit to the Green EVAP System Service Port
located on the EVAP Purge VSV line in the engine compartment.
D) Using the directions on the inside of the EVAP System Pressure Test Kit lid, pressurize the EVAP
system. Once pressurized, turn off the pump and seal the system (Pressure Hold Switch to ªClosedº
and Vent Switch to ªClosed).
E) After 30 seconds, note the pump pressure gauge reading and the Scan Tool vapor pressure
sensor reading.
F) Compare the readings to one of the four conditions listed below and proceed as directed.
DO NOT PROCEED! NG
OK
SCAN TOOL SETUP
A) Connect Scan Tool to DLC3 on vehicle.
B) Go to the SETUP menu and select UNIT CONVERSION.
C) Under VAPOR PRESSURE, Select ABS for absolute pressure, and mmHg for millimeters of mercury.
This is to match the Repair Manual specifications.
D) Go back to FUNCTION SELECT menu and select ENHANCED OBD II.
E) Select NORMAL MODE. Then select CURRENT DATA and USER SELECT.
F) Using the arrow key, select VAPOR PRESS from the DATA LIST and select YES.
G) Press ENTER. You will now be able to monitor the Vapor Pressure Sensor reading.
START
If vehicle is ECHO, go directly to ªECHO Canister and Tank Leak Checkº on page 14.
If vehicle is not ECHO, follow the flow chart below.
Diagnostic
Tips for Late
Type EVAP
System
(Continued)

EVAP SYSTEM OPERATION INFORMATION ± EG005-01 April 27, 2001
Page 12 of 14
Pump pressure
gauge and vapor
pressure above
atmospheric
pressure (above 762
mmHg). No leak in
canister or tank.Pump pressure
gauge zero, vapor
pressure above
atmospheric
pressure (above 762
mmHg). Leak is on
canister side of
system.Pump pressure
gauge is above
atmospheric
pressure (above
zero), vapor
pressure is at
762 mmHg. Leak is
on the fuel tank side
of system.Pump pressure
gauge at zero,
vapor pressure is
at 762 mmHg. The
leak(s) is/are on the
canister and tank
sides or a leak at a
point common to
both sides of system.
Remove hose pliers
from the air drain
hose on the charcoal
canister before
proceeding with
additional checks.Remove hose pliers
from the air drain
hose on the charcoal
canister before
proceeding with
additional checks.Remove hose pliers
from the air drain
hose on the charcoal
canister before
proceeding with
additional checks.
Go to CCV/Air Inlet
Line Check.Go to ªCanister Leak
Check.º Diagram on
page 13.Go to ªFuel Tank
Leak Check.º
Diagram on page 13.Go to ªFuel Tank
Leak Check.º
Diagram on page 13.
Remove hose pliers
from the air drain
hose on the charcoal
canister before
proceeding with
additional checks.
Go to ªReturn Vehicle to Serviceº on page 14.
CCV and Air Inlet Line Check. (Except ECHO)
A) Disconnect the air inlet line from the charcoal canister.
B) Using the supplied step±down brass adapter (or equivalent) connect the Pressure Supply Hose to
the air inlet line.
C) Using the Scan Tool Active Test, turn on the CCV. This will close the CCV.
D) Pressurize the line. Once pressurized, turn off the pump and seal the line (Pressure Hold Switch to
ªClosedº and Vent Switch to ªClosedº). Pressure should hold. If not, check CCV and connections.
E) Next, using the Scan Tool, turn off the CCV. This will open the CCV. The pressure should decrease.
If not, check the CCV and connections.
F) After completing the test, reconnect air inlet line to charcoal canister. Diagnostic Process Flow Chart (Continued)
(Continued from previous page)
Diagnostic
Tips for Late
Type EVAP
System
(Continued)

EVAP SYSTEM OPERATION INFORMATION ± EG005-01 April 27, 2001
Page 13 of 14
Disconnect
EVAP Hose Here
A. Using the supplied brass step±down adapter, disconnect the EVAP hose from
the charcoal canister side as indicated above. Connect Pressure Supply hose
from Pressure Test Kit to the EVAP hose and pressurize the fuel tank to
30 mmHg (4 kPa / 0.58 psi).
B. Check that the internal pressure of the tank will hold for 1 minute. Check shaded
areas for leaks (soapy water can be used for leak detection). If pressure holds, then
perform the Canister Leak Check.
C. When done, reconnect the EVAP line hose to the charcoal canister. Fuel Tank Leak Check (Except ECHO)
Canister Leak Check (Except ECHO)
A. Connect the Pressure Supply hose from the Pressure Test Kit to the Green EVAP
System Service Port located on the EVAP Purge VSV line in the engine compartment.
B. Using the directions on the inside of the EVAP System Pressure Test Kit lid,
pressurize the EVAP system. Once pressurized, turn off the pump and seal the system
(Pressure Hold Switch to ªClosedº and Vent Switch to ªClosedº)
C. With system pressurized at EVAP Service Port, check shaded areas for leaks (soapy
water can be used for leak detection). Diagnostic
Tips for Late
Type EVAP
System
(Continued)

M.I.L. ªONº P0440, P0441 & P0446 ± EG013-02July 12, 2002
Page 2 of 5
Test VSV Operation Using ACTIVE TEST on the Toyota Diagnostic Tester
1. Test operation of the Vapor Pressure Sensor VSV using the Toyota Diagnostic Tester
in ACTIVE TEST (see screen flow in Figure 1).
INJECTOR 0.0ms
IGN ADVANCE 5.0deg
CALC LOAD 0%
MAF 0gm/s
ENGINE SPD 0rpm
COOLANT TEMP 77.0F
INTAKE AIR 87.8F
THROTTLE POS 16%
CTP SW ON
VEHICLE SPD 0MPH
02S B1 S1 0.00V
2: CUSTOMIZE
3: ECU REPROGRAMFUNCTION SELECT FOR
NORTH AMERICA
B
*APPLICATION SELECT*
A
1: DIAGNOSISDIAGNOSTIC MENU
ENGINE
C
PRESS INJ VOL
A/F CONTROL
FUEL PMP SP CTL
A/C CUT SIG
CAN CTRL VSV
EVAP VSV (ALONE)
FUEL PUMP/SPD
LINE PRESS UPSELECT DATA
E
SELECT DATA
D
TANK BYPASS VSVUSER DATA
[ENTER]
F
G
TANK BYPASS VSV OFF
1: OBD/MOBD
3: CARB OBD II
4: BREAK±OUT BOX
5: NVH
6: AUTOPROBE
7: 02 RPM CHECK
8: SNAPSHOT REVIEW
9: SETUP
0: GAS ANALYSIS2: ENHANCED OBD1: DATA LIST
2: DTC INFO
4: SNAPSHOT
5: SYSTEM CHECK
6: RESET MEMORY
7: MONITOR STATUS
8: CHECK MODE
3: ACTIVE TEST
ALL
INJECTOR 0.0ms
IGN ADVANCE 5.0deg
CALC LOAD 0%
MAF 0gm/s
ENGINE SPD 0rpm
COOLANT TEMP 77.0F
INTAKE AIR 87.8F
THROTTLE POS 16%
CTP SW ON
VEHICLE SPD 0MPH
02S B1 S1 0.00V Figure 1: Testing Operation of Vapor Pressure Sensor VSV using ACTIVE TEST
TANK BYPASS VSV ON
NOTE:
Vapor Pressure Sensor VSV is listed as TANK BYPASS VSV on the Diagnostic Tester. Inspection &
Repair
Procedure

G ELECTRICAL WIRING ROUTING
Position of Parts in Engine Compartment
A 1 A/C Condenser Fan Motor
A 2 A/C Magnetic Clutch and Lock Sensor
A 3 A/C Triple Pressure SW
(A/C Dual and Single Pressure SW)
A 4 ABS Actuator
A 5 ABS Actuator
A 6 ABS Speed Sensor Front LH
A 7 ABS Speed Sensor Front RH
A 8 Air Fuel Ratio Sensor
A 9 Airbag Sensor Front LH
A 10 Airbag Sensor Front RH
B 1 Brake Fluid Level Warning SW
C 1 Camshaft Position Sensor
C 2 Crankshaft Position Sensor
C 3 Cruise Control Actuator
D 1 Data Link Connector 1
E 1 Electronically Controlled Transmission Solenoid
E 2 Electronically Controlled Transmission Solenoid
E 3 Engine Coolant Temp. SensorF 1 Front Turn Signal Light and Parking Light LH
F 2 Front Turn Signal Light and Parking Light RH
F 3 Front Wiper Motor
F 4 Fuel Pressure Sensor (Delivery Pipe)
F 5 Fuel Pressure Sensor (Fuel Pipe)
F 6 Fuel Shutoff Valve (Delivery Pipe)
F 7 Fuel Shutoff Valve (Fuel Pressure Regulator)
F 8 Fuel Temp. Sensor (Delivery Pipe)
F 9 Fusible Link Block
F 10 Fusible Link Block
F 11 Fusible Link Block
F 12 Fusible Link Block
F 13 Fusible Link Block
F 14 Fusible Link Block
G 1 Generator
G 2 Generator
H 1 Headlight LH
H 2 Headlight RH
H 3 Horn (High)
H 4 Horn (Low)

ENGINE CONTROL
1 2
1 2
2 1
I 4
I 4 C 10 C23 D4 D 9A 2B14 B6
B 1
B 9
B 11
B 2
B 3
B 4
1 2
1 2 1 314 B B B B
2 3 1 223 BB
BR
B±Y B±YBR B±Y B±Y
BR Y
G±BY±B BRB±YY
LG
BR BRYW±B
W
P±B
P
G
BRB B±Y B±Y B±Y
PIM VC E2
VC VTA E2J18
JUNCTION
CONNECTOR
IDLE AIR CONTROL VALVE
VSV (
EGR)
FUEL SHUTOFF VAL VE
(
DELIVERY PIPE) FUEL SHUTOFF VALVE
(
FUEL PRESSURE
REGULATOR)
AIR FUEL RATIO SENSOR I 1
V 2
F 6F 7
A 8
MANIFOLD ABSOLUTE
PRESSURE SENSOR M 1
INTAKE AIR TEMP. SENSOR
ENGINE COOLANT TEMP. SENSOR I 8
E 3
ENGINE CONTROL MODULEB E 4 E 5ACE 6
(
SHIELDED)
+B AF +
AF± HT L±B
IG1 6
L±B Y±G
2
IB1Y
BR, , DE 7 ,
I 5 IG23
BR
THROTTLE
POSITION
SENSOR T 1BR
B±W
L
IG1 7
G
D 5D7
I 4D 6
23 23
11
G± BY
G±R
Y BR
BR BR
P±B BR
2
1
FUEL TEMP. SENSOR
(
DELIVERY PIPE) F 8
BR W±B
BR
PCNG2 PCNG1 VC VTA E2 PIM THA THW THCNG2 VCNG2 RSD EGR VCNG3 HTAF AF± AF+
BR
LGY
132
Y
B± Y
L
VOUT VC VOUT VC
GND GND
FUEL PRESSURE SENSOR
(
DELIVERY PIPE) F 4
FUEL PRESSURE SENSOR
(
FUEL PIPE) F 5
I 4I 4 I 4 I 4 BR BR BR BR

This system utilizes an engine control module and maintains overall control of the engine, transmission and so on. An outline
of the engine control is explained here.
1. INPUT SIGNALS
(1) Engine coolant temp. signal circuit
The engine coolant temp. sensor detects the engine coolant temp. and has a built±in thermistor with a resistance which
varies according to the engine coolant temp. thus the engine coolant temp. is input in the form of a control signal into
TERMINAL THW of the engine control module.
(2) Intake air temp. signal circuit
The intake air temp. sensor detects the intake air temp. , which is input as a control signal into TERMINAL THA of the
engine control module.
(3) Oxygen sensor signal circuit
The oxygen density in the exhaust gases is detected and input as a control signal into TERMINAL OX2 of the engine
control module.
(4) RPM signal circuit
Camshaft position and crankshaft position are detected by the camshaft position sensor and crankshaft position sensor.
Camshaft position is input as a control signal to TERMINAL G of the engine control module, and engine RPM is input
into TERMINAL NE.
(5) Throttle signal circuit
The throttle position sensor detects the throttle valve opening angle, which is input as a control signal into TERMINAL
VTA of the engine control module.
(6) Vehicle speed signal circuit
The vehicle speed sensor, installed inside the transmission, detects the vehicle speed and inputs a control signal into
TERMINAL SPD of the engine control module.
(7) Park/Neutral position SW signal circuit
The Park/Neutral position SW detects whether the shift position are in neutral, parking or not, and inputs a control signal
into TERMINAL STA of the engine control module.
(8) A/C SW signal circuit
The A/C amplifier is built in the engine control module. The signal from the A/C SW is input into TERMINAL A/CS of the
engine control module.
(9) Battery signal circuit
Voltage is constantly applied to TERMINAL BATT of the engine control module. When the ignition SW is turned on, the
voltage for engine control module start±up power supply is applied to TERMINAL +B of engine control module via EFI
relay.
(10) Intake air volume signal circuit
Intake air volume is detected by the manifold absolute pressure sensor (for manifold pressure) and is input as a control
signal into TERMINAL PIM of the engine control module.
(11) Starter signal circuit
To confirm whether the engine is cranking, the voltage applied to the starter motor during cranking is detected and the
signal is input into TERMINAL NSW of the engine control module as a control signal.
(12) Electrical load signal circuit
The signal when systems such as the rear window defogger, headlights, etc. Which cause a high electrical burden are
on is input to TERMINAL ELS as a control signal.
(13) Air fuel ratio signal circuit
The air fuel ratio is detected and input as a control signal into TERMINAL AF+ of the engine control module.
SYSTEM OUTLINE