Subaru 2001 IMPREZA User manual

FUJI HEAVY INDUSTRIES LTD. G1830GE3
2001 IMPREZA SERVICE MANUAL QUICK REFERENCE INDEX
ENGINE 2 SECTION
This service manual has been prepared
to provide SUBARU service personnel
with the necessary information and data
for the correct maintenance and repair
of SUBARU vehicles.
This manual includes the procedures
for maintenance, disassembling, reas-
sembling, inspection and adjustment of
components and diagnostics for guid-
ance of experienced mechanics.
Please peruse and utilize this manual
fully to ensure complete repair work for
satisfying our customers by keeping
their vehicle in optimum condition.
When replacement of parts during
repair work is needed, be sure to use
SUBARU genuine parts.
All information, illustration and specifi-
cations contained in this manual are
based on the latest product information
available at the time of publication
approval.
FUEL INJECTION (FUEL SYSTEMS) FU(SOHCw/oOBD)
EMISSION CONTROL
(AUX. EMISSION CONTROL DEVICES) EC(SOHCw/oOBD)
EXHAUST EX(SOHCw/oOBD)
IGNITION IG(SOHCw/oOBD)
ENGINE(DIAGNOSTICS) EN(SOHCw/oOBD)
FUEL INJECTION (FUEL SYSTEMS) FU(DOHC TURBO)
EMISSION CONTROL
(AUX. EMISSION CONTROL DEVICES) EC(DOHC TURBO)
INTAKE (INDUCTION) IN(DOHC TURBO)
MECHANICAL ME(DOHC TURBO)
EXHAUST EX(DOHC TURBO)
IGNITION IG(DOHC TURBO)
ENGINE (DIAGNOSTICS) EN(DOHC TURBO)

FUEL INJECTION (FUEL SYSTEMS)
FU(SOHCw/oOBD)
Page
1. General Description ....................................................................................2
2. Throttle Body.............................................................................................14
3. Intake Manifold..........................................................................................15
4. Engine Coolant Temperature Sensor........................................................27
5. Crankshaft Position Sensor.......................................................................28
6. Camshaft Position Sensor.........................................................................29
7. Knock Sensor............................................................................................30
8. Throttle Position Sensor............................................................................31
9. Intake Air Temperature and Pressure Sensor...........................................34
10. Idle Air Control Solenoid Valve .................................................................35
11. Fuel Injector ..............................................................................................36
12. Oxygen Sensor .........................................................................................42
13. Engine Control Module..............................................................................44
14. Main Relay................................................................................................45
15. Fuel Pump Relay.......................................................................................46
16. Fuel...........................................................................................................47
17. Fuel Tank..................................................................................................48
18. Fuel Filler Pipe..........................................................................................50
19. Fuel Pump.................................................................................................54
20. Fuel Level Sensor.....................................................................................56
21. Fuel Filter..................................................................................................57
22. Fuel Cut Valve...........................................................................................58
23. Fuel Damper Valve ...................................................................................59
24. Fuel Delivery, Return and Evaporation Lines............................................60
25. Fuel System Trouble in General ...............................................................63

FU(SOHCw/oOBD)-2
FUEL INJECTION (FUEL SYSTEMS) GENERAL DESCRIPTION
1. General Description
A: SPECIFICATIONS
Model
Fuel tank Capacity 50 2(13.2 US gal, 11.0 Imp gal)
Location Under rear seat
Fuel pump
Type Impeller
Shutoff discharge pressure 370 —677 kPa (3.77 —6.9 kg/cm2, 53.6 —98 psi)
Discharge flow More than 65 2(17.2 US gal, 14.3 Imp gal)/h
[12 V at 300 kPa (3.06 kg/cm2, 43.5 psi)]
Fuel filter Cartridge type

FU(SOHCw/oOBD)-3
FUEL INJECTION (FUEL SYSTEMS)
GENERAL DESCRIPTION

FU(SOHCw/oOBD)-4
FUEL INJECTION (FUEL SYSTEMS) GENERAL DESCRIPTION
B: COMPONENT
1. INTAKE MANIFOLD
EN1002
(21)
(21)
(22)
(20)
(5)
(6)
(7) (8)
(2)
(9) (20)
(13)
(3)
(2)
(4)
(16)
(19)
(17)
(15)
(12)
(11)
(1)
(19)
(19)
(18)
(18)
(18)
(14)
(10)
(23)
(4)
(3)
(5)
T2
T2
T4
T3
T3
T3
T2
T4
T1
T3
T3
T2 T3
T3
T3

FU(SOHCw/oOBD)-5
FUEL INJECTION (FUEL SYSTEMS)
GENERAL DESCRIPTION
(1) Intake manifold gasket RH (11) Intake manifold gasket LH (20) Clip
(2) Fuel injector pipe (12) Fuel pipe protector LH (21) Guide pin
(3) Fuel injector (13) Intake air temperature and pres-
sure sensor (22) Plug cord holder RH
(4) O-ring (23) Accelerator cable bracket
(5) O-ring (14) O-ring
(6) Plug (15) Plug cord holder LH Tightening torque: N·m (kgf-m, ft-lb)
(7) PCV valve (16) Fuel pipe protector RH T1: 3.4 (0.35, 2.5)
(8) Purge control solenoid valve (17) Fuel pipe ASSY T2: 5.0 (0.51, 3.7)
(9) Nipple (18) Fuel hose T3: 19 (0.19, 1.4)
(10) Intake manifold (19) Clip T4: 25 (2.6, 18.8)

FU(SOHCw/oOBD)-6
FUEL INJECTION (FUEL SYSTEMS) GENERAL DESCRIPTION
2. AIR INTAKE SYSTEM
B2M3455C
(1) Gasket (4) Throttle body Tightening torque: N·m (kgf-m, ft-lb)
(2) Throttle position sensor T1: 1.6 (0.16, 1.2)
(3) Idle air control solenoid valve T2: 22 (2.2, 16)

FU(SOHCw/oOBD)-7
FUEL INJECTION (FUEL SYSTEMS)
GENERAL DESCRIPTION
3. CRANKSHAFT POSITION, CAMSHAFT
POSITION AND KNOCK SENSORS
B2M2282B
(1) Crankangle position sensor (3) Camshaft position sensor Tightening torque: N·m (kgf-m, ft-lb)
(2) Knock sensor (4) Camshaft position sensor support T1: 6.4 (0.65, 4.7)
T2: 24 (2.4, 17.4)

FU(SOHCw/oOBD)-8
FUEL INJECTION (FUEL SYSTEMS) GENERAL DESCRIPTION
4. FUEL TANK
EN0439
T1 T1
T3
T2
T2
T2
T3
(6)
(5)
(7)
(8)
(9)
(9)
(8)
(17)
(20)
(11)
(11)
(21)
(11)
(11)
(22)
(23)
(19) (18)
(1)
(2)
(3)
(2)
(4)
AB
(24)
(15)
A
B
T1
DC
D
C
(18)
(11)
(11)
(11)
(12)
(12)
(24)
(12)
(13)
(10)
(16) (25)
(14)
(19)

FU(SOHCw/oOBD)-9
FUEL INJECTION (FUEL SYSTEMS)
GENERAL DESCRIPTION
(1) Heat sealed cover (11) Clip (21) Fuel pipe ASSY
(2) Fuel tank band (12) Evaporation hose B (22) Evaporation hose F
(3) Protector RH (13) Joint pipe (23) Fuel return hose B
(4) Fuel tank (14) Evaporation hose C (24) Evaporation hose G
(5) Fuel pump gasket (15) Evaporation pipe ASSY (25) Evaporation hose H
(6) Fuel pump ASSY (16) Evaporation pipe
(7) Fuel meter unit (17) Evaporation hose D Tightening torque: N·m (kgf-m, ft-lb)
(8) Fuel cut valve gasket (18) Retainer T1: 4.4 (0.45, 3.3)
(9) Fuel cut valve (19) Quick connector T2: 7.4 (0.75, 5.4)
(10) Evaporation hose A (20) Evaporation hose E T3: 33 (3.4, 25)

FU(SOHCw/oOBD)-10
FUEL INJECTION (FUEL SYSTEMS) GENERAL DESCRIPTION
5. FUEL LINE
EN0440
(12)
(11)
(1)
(1)
(1)
(7)
(1)
(1) (9) (10)
(10)
(1)
(6)
(5)
(4) (3)
(2)
(1) (1)
(8)
(24)
(24)
(18)
(23)
(13)
(14)
(1) (1)
(21)
(20)
(25)
(22)
(19)
(17)
(16)
(15)
C
B
B
A
C
A
T

FU(SOHCw/oOBD)-11
FUEL INJECTION (FUEL SYSTEMS)
GENERAL DESCRIPTION
(1) Clip (11) Fuel pipe ASSY (21) Two-way valve drain hose A
(2) Fuel delivery hose A (12) Grommet (22) Connector
(3) Fuel filter bracket (13) Canister hose A (23) Two-way valve drain hose B
(4) Fuel filter holder (14) Canister (24) Clamp
(5) Fuel filter cup (15) Canister bracket plate (25) Front canister bracket
(6) Fuel filter (16) Cushion
(7) Evaporation hose (17) Canister bracket spacer Tightening torque: N·m (kgf-m, ft-lb)
(8) Fuel damper (18) Rear canister bracket T: 23 (2.34, 17.0)
(9) Fuel delivery hose B (19) Two-way valve return hose
(10) Fuel return hose (20) Two-way valve

FU(SOHCw/oOBD)-12
FUEL INJECTION (FUEL SYSTEMS) GENERAL DESCRIPTION
6. FUEL FILLER PIPE
(11)
T
T
(4)
(2)
(8)
(1)
(6)
(3)
(3)
(7)
(9)
(10)
(5)
(3)
T
T
T
EN0441
(1) Fuel filter pipe ASSY (6) Air vent pipe Tightening torque: N·m (kgf-m, ft-lb)
(2) Evaporation hose holder (7) Air vent pipe holder T: 7.5 (0.76, 5.5)
(3) Clamp (8) Filler pipe packing
(4) Clamp (9) Filler ring
(5) Air vent hose (10) Filler cap

FU(SOHCw/oOBD)-13
FUEL INJECTION (FUEL SYSTEMS)
GENERAL DESCRIPTION
C: CAUTION
•Wear working clothing, including a cap, protec-
tive goggles, and protective shoes during opera-
tion.
•Remove contamination including dirt and corro-
sion before removal, installation or disassembly.
•Keep the disassembled parts in order and pro-
tect them from dust or dirt.
•Before removal, installation or disassembly, be
sure to clarify the failure. Avoid unnecessary re-
moval, installation, disassembly, and replacement.
•Be careful not to burn your hands, because each
part on the vehicle is hot after running.
•Be sure to tighten fasteners including bolts and
nuts to the specified torque.
•Place shop jacks or safety stands at the specified
points.
•Before disconnecting electrical connectors of
sensors or units, be sure to disconnect negative
terminal from battery.
•Place “NO FIRE”signs near the working area.
•Be careful not to spill fuel on the floor.
D: PREPARATION TOOL
ILLUSTRATION TOOL NUMBER DESCRIPTION REMARKS
24082AA150
(Newly adopted
tool)
CARTRIDGE Troubleshooting for electrical system.
22771AA030 SELECT MONI-
TOR KIT Troubleshooting for electrical systems. •English: 22771AA030 (Without printer)
•German: 22771AA070 (Without printer)
•French: 22771AA080 (Without printer)
•Spanish: 22771AA090 (Without printer)
B2M3876
B2M3877

FU(SOHCw/oOBD)-14
FUEL INJECTION (FUEL SYSTEMS) THROTTLE BODY
2. Throttle Body
A: REMOVAL
1) Disconnect battery ground cable.
2) Remove air cleaner case.
3) Disconnect accelerator cable (A).
4) Disconnect cruise control cable (B). (With cruise
control model)
5) Disconnect connectors from idle air control sole-
noid valve, throttle position sensor.
6) Disconnect air by-pass hose from air purge con-
trol solenoid valve.
7) Disconnect engine coolant hoses from throttle
body.
8) Remove bolts which install throttle body tointake
manifold.
B: INSTALLATION
Install in the reverse order of removal.
CAUTION:
Always use a new gasket.
Tightening torque:
Throttle body;
22 N·m (2.2 kgf-m, 15.9 ft-lb)
Air cleaner case;
6.5 N·m (0.66 kgf-m, 4.8 ft-lb)
G6M0095
H2M2947
B2M4254A
(A) Throttle position sensor
(B) Idle air control solenoid valve
(C) Air by-pass hose from purge control solenoid
valve
H2M2949
B2M4255

FU(SOHCw/oOBD)-15
FUEL INJECTION (FUEL SYSTEMS)
INTAKE MANIFOLD
3. Intake Manifold
A: REMOVAL
1) Release fuel pressure. <Ref. to FU(SOHCw/
oOBD)-47, RELEASING OF FUEL PRESSURE,
OPERATION, Fuel.>
2) Open fuel flap lid, and remove fuel filler cap.
3) Disconnect battery ground cable.
4) Remove air intake duct and air cleaner assem-
bly. <Ref. to IN(SOHC)-7, REMOVAL, Air Intake
Duct.> and <Ref. to IN(SOHC)-6, REMOVAL, Air
Cleaner Case.>
5) Disconnect accelerator cable (A).
6) Disconnect cruise control cable (B). (With cruise
control model)
7) Remove power steering pump and tank from
brackets.
(1) Remove resonator chamber. <Ref. to
IN(SOHC)-8, REMOVAL, Resonator Cham-
ber.>
(2) Remove front side V-belt. <Ref. to ME(SO-
HC)-42, REMOVAL, V-belt.>
(3) Remove bolts which hold power steering
pipes onto intake manifild protector.
NOTE:
Do not disconnect power steering hose.
(4) Remove bolts which install power steering
pump bracket.
(5) Disconnect connector from power steering
pump switch.
(6) Remove power steering tank from the
bracket by pulling it upwards.
G6M0095
B2M4254A
B2M4126
B2M3151
EN0360
EN0361

FU(SOHCw/oOBD)-16
FUEL INJECTION (FUEL SYSTEMS) INTAKE MANIFOLD
(7) Place power steering pump and tank on the
right side wheel apron.
8) Disconnect spark plug cords from spark plugs.
9) Disconnect PCV hose from intake manifold.
10) Disconnect engine coolant hose from throttle
body.
11) Disconnect brake booster hose.
12) Remove air cleaner case stay RH and engine
harness bracket, and disconnect engine harness
connectors from bulkhead harness connectors.
13) Disconnect connectors from engine coolant
temperature sensor.
14) Disconnect knock sensor connector.
15) Disconnect connector from crankshaft position
sensor.
EN0208
B2M4258
B2M4255
B2M4259
B2M4260
B2M4261
B2M4262
B2M1252

FU(SOHCw/oOBD)-17
FUEL INJECTION (FUEL SYSTEMS)
INTAKE MANIFOLD
16) Disconnect connector from oil pressure switch.
17) Disconnect connector from camshaft position
sensor.
18) Disconnect fuel hoses from fuel pipes.
WARNING:
•Do not spill fuel.
•Catch fuel from hoses in a container or cloth.
19) Remove bolts which hold intake manifold onto
cylinder heads.
20) Remove intake manifold.
B: INSTALLATION
1) Install intake manifold onto cylinder heads.
CAUTION:
Always use new gaskets.
Tightening torque:
25 N·m (2.5 kgf-m, 18.1 ft-lb)
2) Connect fuel hoses.
(A) Fuel delivery hose
(B) Return hose
(C) Evaporation hose
B2M1253
B2M4263
S2M0500F
B2M4128
(A) Fuel delivery hose
(B) Return hose
(C) Evaporation hose
B2M0160
B2M4128
S2M0500F

FU(SOHCw/oOBD)-18
FUEL INJECTION (FUEL SYSTEMS) INTAKE MANIFOLD
3) Connect connector to camshaft position sensor.
4) Connect connector to oil pressure switch.
5) Connect connector to crankshaft position sen-
sor.
6) Connect knock sensor connector.
7) Connect connectors to engine coolant tempera-
ture sensor.
8) Install air cleaner case stay RH and engine har-
ness bracket, and connect engine harness connec-
tors to bulkhead connectors.
9) Connect brake booster hose.
10) Connect engine coolant hose to throttle body.
B2M4263
B2M1253
B2M1252
B2M4262
B2M4261
B2M4260
B2M4259
B2M4255

FU(SOHCw/oOBD)-19
FUEL INJECTION (FUEL SYSTEMS)
INTAKE MANIFOLD
11) Connect PCV hose to intake manifold.
12) Connect spark plug cords to spark plugs.
13) Install power steering pump and tank on brack-
ets.
(1) Install power steering tank on bracket.
(2) Connect connector to power steering pump
switch.
(3) Tighten bolts which install power steering
pump on bracket.
Tightening torque:
20.1 N·m (2.05 kgf-m, 14.8 ft-lb)
(4) Install power steering pipes onto right side
intake manifold protector.
(5) Install V-belt. <Ref. to ME(SOHC)-42, IN-
STALLATION, V-belt.>
(6) Install resonator chamber.
Tightening torque:
33 N·m (3.4 kgf-m, 24.6 ft-lb)
14) Connect accelerator cable (A).
15) Connect cruise control cable (B). (With cruise
control models)
16) Install air intake duct and air cleaner assembly.
<Ref. to IN(SOHC)-7, INSTALLATION, Air Intake
Duct.> and <Ref. to IN(SOHC)-6, INSTALLATION,
Air Cleaner Case.>
B2M4258
EN0361
EN0360
B2M3151
B2M4126
B6M1237
B2M4254A