evap LEXUS SC400 1991 Service Manual PDF

15. DISCONNECT ENGINE WIRE CONNECTORS
16. DISCONNECT THEFT DETERRENT HORN CONNECTOR
17. DISCONNECT GROUND CABLE FROM BODY
18. DISCONNECT PS SOLENOID VALVE CONNECTOR
19. DISCONNECT WIRE CLAMP (FOR ALTERNATOR) FROMVSV (FOR EVAP SYSTEM)
(a) Remove the two bolts, and disconnect the VSV from the
RH cylinder head.
(b) Disconnect the wire clamp from the VSV bracket.
20. REMOVE ALTERNATOR (a) Disconnect the alternator connector.
(b) Remove the cap and nut, and disconnect the alternatorwire.
(c) Remove the mounting bolt and nut.
(d) Disconnect the A/T oil cooler pipe bracket.
(e) Remove the alternator.
21. D I S C O N N E C T P S T U B E S F R O M S U SPENSION
CROSSMEMBER
Remove the clamp bolt, and disconnect the PS tubes.
EM±122
±
ENGINE MECHANICAL Cylinder Block
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17. INSTALL PS TUBESInstall the PS tube clamp with the bolt.
18. INSTALL ALTERNATOR (a) Install the alternator and A/T oil cooler pipe bracket withthe bolt and nut.
Torque: 37 N Vm (380 kgf Vcm, 27 ft Vlbf)
(b) Connect the alternator connector.
(c) Connect the alternator wire with the nut and cap.
19. INSTALL WIRE CLAMP (FOR ALTERNATOR) AND VSV (FOR EVAP SYSTEM)
(a) Install the wire clamp to the VSV bracket.
(b) Install the VSV with the two bolts.
20. CONNECT PS SOLENOID VALVE CONNECTOR
21. CONNECT ENGINE WIRE CONNECTORS
22. CONNECT THEFT DETERRENT HORN CONNECTOR
23. INSTALL GROUND CABLE TO BODY
±
ENGINE MECHANICAL Cylinder BlockEM±173
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ELECTRONIC CONTROL SYSTEM
The control system consists of sensors which detect various engine conditions, and a ECU which deter\
-
mines the injection volume (timing) based on the signals from the sens\
ors.
The various sensors detect the air intake volume, engine rpm, oxygen densit\
y in the exhaust gas, coolant
temperature, air intake temperature and atmospheric pressure etc. and convert the in\
formation into an electrical
signal which is sent to the ECU. Based on these signals, the ECU calculates th\
e optimum ignition timing for the
current conditions and operates the injectors.
The ECU not only controls the fuel injection timing, but also the self diag\
nostic function which records the
occurrence of a malfunction, ignition timing control, idle rpm control, \
EGR control, EVAP control, fuel pressure
control and fuel pump control. FI±9
EFI SYSTEM
± Operation
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6. REMOVE UPPER HIGH±TENSION CORD COVER(a) Remove the two mounting bolts.
(b) Disconnect the front side claw groove of the cord coverfrom the claw of the lower cover, and remove the cord
cover.
7. REMOVE RH ENGINE WIRE COVER Remove the bolt and wire cover.
8. REMOVE LH ENGINE WIRE COVER Remove the two bolts and wire cover.
9. REMOVE VSV FOR EVAP SYSTEM Remove the two bolts, and disconnect the VSV from cylinder
head and timing belt cover.
10. REMOVE RH NO.3 TIMING BELT COVER Remove the three bolts and timing belt cover.
FI±28
EFI SYSTEM
± Fuel System (Cold Start Injector)
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15. DISCONNECT HOSESDisconnect the following hoses:(1) Water by±pass hose (from water inlet housing) from ISC valve
(2) Vacuum hose (from PS air control valve) from air in-
take chamber
(3) Vacuum sensing hose (from fuel pressure regula- tor) from vacuum pipe
(4) Two vacuum hoses (from VSV for EVAP system) from vacuum pipe
(5) Vacuum hose (from charcoal canister) from vacu- um pipe
(6) Water by±pass hose (from EGR valve) from water by±pass pipe
(7) Vacuum hose (from brake booster) from air intake
chamber
(8) Vacuum hose (from VSV for heater water valve) from air intake chamber
(9) PCV hose from LH cylinder head cover
16. REMOVE AIR INTAKE CHAMBER (a) Remove the bolt, stud bolt and accelerator bracket. FI±31
EFI SYSTEM
± Fuel System (Cold Start Injector)
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(g) Install the accelerator bracket with the bolt and stud bolt.
3. CONNECT HOSES Connect the following hoses:(1) Water by±pass hose (from EGR valve) to water by±
pass pipe
(2) Vacuum hose (from brake booster) to air intake chamber
(3) Vacuum hose (from VSV for heater water valve) to
air intake chamber
(4) PCV hose to LH cylinder head cover
(5) Water by±pass hose (from water inlet housing) to ISC valve
(6) Vacuum hose (from PS air control valve) to air in- take chamber
(7) Vacuum sensing hose (from fuel pressure regula- tor) to vacuum pipe
(8) Two vacuum hoses (from VSV for EVAP system) to
vacuum pipe
(9) Vacuum hose (from charcoal canister) to vacuum pipe FI±37
EFI SYSTEM
± Fuel System (Cold Start Injector)
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8. INSTALL VSV FOR EVAP SYSTEMInstall the VSV with the two bolts.
9. INSTALL LH NO.3 TIMING BELT COVER (a) Install the three gaskets to the timing belt cover.
(b) Install the cord grommet to the high±tension cord.
(c) Install the cord grommet to the timing belt cover.
(d) Fit portion A of the timing belt cover, matching it with the
lower high±tension cord cover.
(e) Install the timing belt cover with the four bolts.
10. INSTALL RH ENGINE WIRE COVER (a) Fit portions A and B of the engine wire cover, matching
them with the lower high±tension cord cover and No.3
timing belt cover.
(d) Install the engine wire cover with the bolt.
11. INSTALL LH ENGINE WIRE COVER (a) Connect portions A and B engine wire cover to the wirebrackets.
(b) Set the VSV (for fuel pressure control system) wire in original position.
(c) Fit portions C and D of the engine wire cover, matching them with the lower high±tension cord cover and No.3
timing belt cover.
(d) Install the engine wire cover with the two bolts.
12. INSTALL UPPER HIGH±TENSION CORD COVER (a) Fit portion A of the upper high±tension cover, matching
it with the top of the lower high±tension cord cover.
FI±40
EFI SYSTEM
± Fuel System (Cold Start Injector)
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VSV for EVAP
INSPECTION OF VSV FOR EVAP
(See Emission Control System on page EC±11) FI±95
± Electronic Control System (VSV f\
or EVAP)EFI SYSTEM
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TERMINALS OF ENGINE & ECT ECU (Cont'd)
TerminalNo.SymbolConnectionTerminalNo.SymbolConnection
E10± 21NCOT/M Input Speed SensorE10 ± 51±
22±52HTL2LH Sub±Oxygen Sensor Heater
23SP2No.2 Speed Sensor for ECT53HTR2RH Sub±Oxygen Sensor Heater
24±54±
25G2LH (No.2) Cam Position Sensor55±
26G1RH (No.1) Cam Position Sensor56IGT2No.2 Igniter for RH Bank
27NEEngine Speed Sensor57IGT1No.1 Igniter for LH Bank
28VF2Check Connector58IGF1No.1 Igniter for LH Bank
29VF1Check Connector59IGF2No.2 Igniter for RH Bank
30±60±
31±61±
32ISC4ISC Valve62±
33ISC3ISC Valve63IDL2Sub±Throttle Position Sensor
34ISC2ISC Valve64IDL1Throttle Position Sensor
35ISC1ISC Valve65E2Sensor Ground
36* EGR4EGR Valve66KSAir Flow Meter
37* EGR3EGR Valve67OXR2
38* EGR2EGR Valve68OXL2LH Sub±Oxygen Sensor
39* EGR1EGR Valve69E1ECU Ground39* EGRVSV for EGR69E1ECU Ground
40±70±
41VCThrottle Position Sensor
Air Flow Meter71HTL1LH Main Oxygen Sensor
42VTA2Fuel Pump ECU72HTR1RH Main Oxygen Sensor
43VTA1A/C Magnet Clutch Relay73FPUVSV for Fuel Pressure Control
Value
44THWWater Temp. Sensor74* PA GVSV for EVAP
45THAIntake Air Temp. Sensor75±
46THGEGR Gas Temp. Sensor76NSWNeutral Start Switch
47OXR1RH Main Oxygen Sensor77STAStarter Relay
48OXL1LH Main Oxygen Sensor78STJCold Start Injector
49KNK2RH (No.2) Knock Sensor79E02Power Ground
50KNK1LH (No.1) Knock Sensor80E01Power Ground
Engine & ECT ECU Terminals
*USA spec. only
*  A/T only
FI±127EFI SYSTEM ± Electronic Control System (Engine & ECT ECU)
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Resistance of ECU Wiring Connectors
TerminalsConditionSTD voltage (V)
#10 (E10 ± 20)
#20 (E10 ± 19)
#30 (E10 ± 18)+ B (E9 ± 31)13 2 14 2#40 (E10 ± 17)±+ B1 (E9 ± 32) ±13.2 ± 14.2
#50 (E10 ± 16)
#60 (E10 ± 15)
ISC1 (E10 ± 35)
ISC2 (E10 ± 34)+ B (E9 ± 31)10 30ISC3 (E10 ± 33)±
+ B1 (E9 ± 32) ±10 ± 30
ISC4 (E10 ± 32)
ACIS (E10 39)+ B (E9 ± 31)38 5 44 5ACIS (E10 ± 39)±
+ B1 (E9 ± 32) ±38.5 ± 44.5
HT (E10 71)+ B (E9 ± 31)51 63HT (E10 ± 71)±
+ B1 (E9 ± 32) ±5.1 ± 6.3
EVAP (E10 74)+ B (E9 ± 31)30 34EVAP (E10 ± 74)±
+ B1 (E9 ± 32) ±30 ± 34
ERG (E10 75)+ B (E9 ± 31)33 39ERG (E10 ± 75)±
+ B1 (E9 ± 32) ±33 ± 39
IDL1 (E10 ± 64)E2 (E10 65)Throttle valve openInfinity
IDL2 (E10 ± 63)± E2 ± (E10 ± 65)Throttle valve fully closed2,300 or less
VTA1 (E10 ± 43)E2 (E10 65)Throttle valve open3,300 ± 10,000
VTA2 (E10 ± 42)± E2 ± (E10 ± 65)Throttle valve fully closed200 ± 800
VC (E10 ± 41)±E2 ± (E10 ± 65)±4,000 ± 9,000
THA (E10 ± 45)±E2 ± (E10 ± 65)Intake air temp. 20
°C (68 °F)2,000 ± 3,000
THW (E10 ± 44)±E2 ± (E10 ± 65)Coolant temp. 80 °C (176 °F)200 ± 400
THG (E10 ± 46)±E2 ± (E10 ± 65)EGR gas temp. 50 °C (112 °F)69,400 ± 88,500
G1 (E10 ± 26)G (E10 7)Camposition sensor 10 + 40°C (14 104°F)125 190G2 (E10 ± 25)±G (E10 ± 7)Cam position sensor ± 10 ± + 40°C (14 ± 104°F)125 ± 190
NE (E10 ± 27)±G (E10 ± 7)Cam position sensor ± 10 ± + 40 °C (14 ± 104 °F)155 ± 240
Engine & ECT ECU Terminals
FI±134EFI SYSTEM ± Electronic Control System (Engine & ECT ECU)
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