INDEX F
1. Resonance duct
Inspection / Replacement.. ........ page F-l 09
2. Air cleaner element
Inspection ................................. page F- 79
Replacement.. ........................... page F-l 09
3. Airflow meter
(With intake air thermosensor)
Inspection
................................. page F-l 68
Replacement.. ........................... page F-l 09
4. Resonance chamber
Inspection I Replacement.. ........ page F-l 09
5. Throttle body
Inspection .................................
page F-l 12
Replacement.. ...........................
page F-l 09
6. Throttle sensor
inspection ................................. page F-l 69
Adjustment..
.............................. page F-l 69
Replacement.. ........................... page F-l 71
7. ISC valve
Inspection ................................. page F-l 16
Replacement..
........................... page F-l 09
8. Dashpot
Inspection ................................. page F-l 42
9. Dynamic chamber
Removal / Installation ................
page F-109
Inspection [DOHC] ................... page F-l 12
10. Air valve
Inspection
................................. page F-l 16
Removal / Installation ................ page F-109
11. Shutter valve actuator
Inspection ................................. page F-l 18
12. Vacuum chamber [DOHC]
Inspection ................................. page F-l 19
13. Intake manifold
Removal / Installation ................ page F-l 09
14. Injector
Inspection .................................
page F-l 31
Removal .................................... page F-131
Installation.. ............................... page F-l 33 15. Pressure regulator
Inspection ................................. page F-l 29
Replacement ............................. page F-l 30
16. Solenoid valve (Pressure regulator control)
[BP1
Inspection ................................. page F-l 35
17. Solenoid valve (VICS) [DOHC]
Inspection ................................. page F-l 18
18. Charcoal canister
Inspection ................................. page F-l 41
19. Solenoid valve (Purge control)
Inspection ................................. page F-l 40
20. Circuit opening relay
Inspection ................................. page F-l 29
Replacement ............................. page F-l 29
21. Engine control unit (ECU)
Removal / Installation ................ page F-l 49
Inspection ................................. page F-149
22. Clutch switch (MTX)
Inspection ................................. page F-l 72
Replacement.. ........................... page F-l 72
23. PCV valve
Inspection ................................. page F-l 38
24. Water thermosensor
Removal / Inspection /
Installation ............................... page F-l 68
25. Fuel filter (High-pressure side)
Replacement.. ........................... page F-l 24
26. Main relay (FUEL INJ relay)
Inspection ................................. page F-l 72
27. Neutral switch (MTX)
inspection ................................. page F-l 73
Replacement.. ........................... page F-l 73
28. Oxygen sensor
Inspection ................................. page F-l 71
Replacement ............................. page F-l 72
29. Power steering pressure switch
Inspection ................................. page F-l 73
Replacement.. ........................... page F-l 73
23UOFX-002
F-3
EGI MT l ENGINE CONTROL SYSTEM(3/3) <>. .DOHC
INSTRUMENT
(SECTION E-3)
EXCEPT
SECTION G) LAMPS
(SECTION 1-4)
-01 ENGINE CONTROL UNIT(EM1
1” is 10 10 iw 1K 11 1G 1E ic 1A 61-19 AIRFLOW METER (EM)
2Y 2w 2” 25 20 20 2M 2K 21 26 2E
2c 2A
X G/W Y/B V L/R * i/o Y G/ x ‘I;’ W /L B/O
L/B * W/B W/Y W/R * W/L Y/B G/O X R/B R/L G/ * “F’ P /0 B/O
1.l 1H IF ID IS
22 2x 2v 2T 2R 2P 2N 2L 2J 2H 2F 20 26
-20 THROTTLE SENSOR 81-21 CLUTCH SWITCH fF)
(EM) El-22 NEUTRAL SWITCH (EM1
F OUTLINE
COMPONENT DESCRIPTIONS
Component
Air cleaner
Airflow meter
Mr valve
Atmospheric pressure
Sensor
Catalytic converter Function Remark
Filters air entering throttle body
Detects amount of intake air; sends signal to intake air thermosensor and fuel pump
ECU switch included
Supplies bypass air into dynamic chamber
l Engine speed increased to shorten
when engine is cold warm-up period
l Thermowax type l Installed in dynamic chamber
Detects atmospheric pressure; sends signal Built in ECU
to ECU
Reduces HC, CO, and NOx by chemical Monolith type
reaction Charcoal canister
Stores fuel tank fumes while engine stopped Check valve
Controls pressure in fuel tank Two-way type Circuit opening relay
Voltage for fuel pump while engine running Clutch switch (MTX)
Detects clutch condition; sends signal to Switch OFF when clutch pedal released
ECU Diagnosis connector
Concentrated service connector 25pin (located near left suspension mount-
Concentrated terminals: ing block)
1. EGI self-diagnostic terminal
2. EC-AT self-diagnostic terminal
3. Test terminal
4. Fuel pump check terminal
5. Cooling fan check terminal
6. Engine rpm output terminal Dynamic chamber
Interconnects all cylinders Engine control unit (ECU) Detects the following:
1. A/C operation 1. A/C switch
2. Air/fuel ratio (Oxygen concentration) 2. Oxygen sensor
3. ATF thermosensor
4. Atmospheric pressure 4. Atmospheric pressure sensor
5. Braking signal 5. Stoplight switch (MTX)
6. Cranking signal 6. Ignition switch (START Position)
7. DRL (Daytime Running Light) operation 7. DRL relay (Canada)
8. E/L operation 8. Blower motor switch, cooling fan relay,
headlight switch, and rear window
defroster switch
9. Engine coolant temperature 9. Water thermosensor
10. Engine speed 10. Distributor (Ne-signal)
11. Ignition ON signal 11. Ignition switch
12. In-gear condition 12. Neutral and clutch switches (MTX)
13. Inhibitor switch (ATX) 13. N range, D range, S range, L range
switch
14. Intake air amount 14. Airflow meter
15. Intake air temperature 15. Intake air thermosensor
(In airflow meter)
16. No.1 piston TDC of compression
17. P/S operation
18. Shift solenoid (ATX)
19. Test signal (Ignition timing, idle speed,
Malfunction code No.)
20. Throttle valve fully closed/fully open
condition 16. Distributor (G-signal) DOHC)
17. P/S pressure switch
18. 1-2, 2-3, 3-4, Lockup solenoid
19. Diagnosis connector
(TEN terminal)
20. Throttle sensor (MTX)
21. Throttle valve opening angle
22. Turbine sensor 21. Throttle sensor (ATX) .__r
F-10
F TROUBLESHOOTING GUIDE
RELATIONSHIP CHART
OUTPUT DEVICE
INPUT DEVICE
DIAGNOSIS CONNECTOR
[TEN TERMINAL) 0 0 0 0
IGNITION SWITCH (START POSITION) 0 0 0 0 0 0
E/L SIGNALg4 0
0
P/S PRESSURE SWITCH 0 0
B/C SWITCH 0 0 0
INHIBITOR SWITCH (ATX) 0 0 0 0 0 0 0
NEUTRALANDCLUTCH
SWITCHES (MTX) 0 0 0 0 0 0 0
STOPLIGHT SWITCH 0
0
&TMOSPHERIC PRESSURE SENSOR
[IN ECU) o 0 0 0 0
rHROTTLE SENSOR 0 0 0 0 0 0 0
INTAKE AIR THERMOSENSOR 0 0 0 0 0
MRFLOW METER 0 0 0 0 0
3XYGEN SENSOR 0 0 0 0
JVATERTHERMOSENSOR 0 0 0 0 0 0 0
G-SIGNAL*’ 0 0
3ISTRIBUTOR
Ne-SIGNAL 0 0 0 0 0 0 0 0
-- ,.-, ,--., ,.*
+z
*3 &HC
MIL: Malfunction Indicator Lamp
r.9u”rn-” I
*’ E/L SIGNAL: Blower fan control switch second position or higher, cooling fan operating, headlights ON, or rear win-
dow defroster switch ON
F-24
TROUBLESHOOTING GUIDE F
9 LACK OF POWER
_-- --
L L -
ESCRIP- *Performance poor under load when throttle valve wide open
ION *Reduced maximum speed
* Idle condition normal
VtOUBLESHOOTlNG HINTS]
) Factors other than engine malfunction
*Clutch slipping
* ATX slipping
l Brake dragging l Low tire pressure
l Incorrect We size l Overloaded
‘, Low intake air amount @ Air/Fuel mixture too lean
l Fuel line pressure decreases l Fuel injection malfunction
@ Poor ignition
@ Low engine compression
@ Alcohol blended fuel used
l Throttle valve not open fully
*Clogged intake air system
l Low tire pressure CY Section H
CY Section K
cz7 Section P
c7 Section Q
w page F-l 14
CT= page F-l 12
Checker with ignition switch ON
w page F-83
rminal 1F voltage CT page F-150
Specification: Battery voltage
(Ignition switch ON)
* If OK, replace ECU w page F-149
c3 If not OK, check wiring between
ECU and Self-Diagnosis Checker
Ignition timing (BTDC)
l BP DOHC : 9*-l lo l BP SOHC
: 4O-8O 4 If advances, go to next step
* If not advance, check ECU terminal
w page F-150
F-61
TROUBLESHOOTING GUIDE F
20 POOR ACCELERATION
DESCRIP- l Performance poor while accelerating
TION l idle condition normal [TROUBLESHOOTING HINTS)
3 Factors other than engine malfunction @ Air/Fuel mixture too lean
*Clutch slipping l Fuel line pressure decreases l ATX slipping l Fuel injection malfunction
l Brake dragging @ Poor ignition l Low tire pressure
@ Low engine compression
l Incorrect tire size @ Alcohol blended fuel used l Over-loaded
3 Low intake arr amount
*Throttle valve not open fully
*Clogging in intake air system
Check factors other than engine CT Section H
c7 Section
P
ing accelerator fully w page F-l 14
w page F-l 12
Checker with ignition switch ON w page F-83
rminal 1 F voltage w page F-150
Specification: Battery voltage
(Ignition switch ON)
W: SELF TEST c3 If OK, replace ECU w page F-149 r;3 If not OK, check wiring between
ECU and Self-Diagnosis Checker
Clearance between throttle
lever and stopper
0.1 mm (0.004 in)
l.Omm (0.039 in)
O.lmm (0.004 in)
0.6mm (0.024 in)
TROUBLESHOOTING GUIDE F
26 POOR FUEL ECONOMY
DESCRIP-
l Fuel economy unsatisfactory TION
[TROUBLESHOOTING HINTS]
While fuel consumption is drastically increased by city driving, short-run operation, stop and go driving, extended winter
warm-up periods, etc., as opposed to “trip” mileage, an attempt should be made to determine these factors when con-
fronted with “poor mileage” conditions. However, since the operator is not always at fault, the following is offered.
@II Operator depressing accelerator more than usual due to
@ Air/Fuel mixture too rich
low engine power
l Poor ignition *High fuel line pressure
@ Alcohol blended fuel used
*Low intake air amount
l Electronic spark advance control system malfunction @ High vehicle load l Low tire pressure
*Clutch slipping/ATX slipping l Incorrect tire size l Exhaust component restricted l Brake dragging ;TEP
INSPECTION ACTION
1
Check factors other than engine Yes
Go to next step
l Low tire pressure = Section Q 9 Unrecommended tire srze v Section Q l Clutch slipping w Section H l Brake dragging No
0 Section P Repair
l Exhaust component restricted cz= page F-136
2
Check if air hoses are connected correctly - Yes
Go to next step CI page F-109
No
Repair 3
Check if “00” IS displayed on Self-Diagnosis
Yes
Checker with ignition switch ON Go to next step W page F-82 No
SYSTEM SELECT: 1 Service Code No. displayed Check for cause (Refer to specified
check sequence) w page F-63
“88” flashes
Check ECU terminal 1F voltage w page F-150
Specification: Battery voltage
(Ignition switch ON)
* If OK, replace ECU CT= page F-149 e If not OK, check wiring between
ECU and Self-Diagnosis Checker 4
Check for correct intake manifold vacuum at idle
Yes Go to next step Vacuum: More than 450 mmHg (17.7 inHg) No
Check for air leakage at intake air sys-
tem components 5
Check if air cleaner element is clean Yes
Go to next step CT= page F-79
No
Replace air cleaner element
F-75
TROUBLESHOOTING GUIDE
27 MIL ALWAYS ON
DESCRIP- *Self-Diagnosis Checker does not indicate Malfunction Code No. but MIL always ON
TION
[TROUBLESHOOTING HINTS]
*Short circuit in wiring harness
l ECU malfunction
iTEF 1
1
-
s
Disconnect (Y/B) wire from ECU and check if
MIL goes off
‘YIB
ATX YIB
INSPECTION ACTION
Yes Replace ECU CT page F-149
No Check for short circuit in wiring be-
tween instrument cluster and ECU
23UOFX-042
28
MIL NEVER ON
IESCRIP- *Self-Diagnosis Checker indicates Malfunction Code No. of input device but MIL never ON
RON *Other indicator and warning lamps OK
:TROUBLESHOOTING HINTS]
b Bulb burned
‘Open circuit in wiring harness
m ECU malfunction
TEP INSPECTION
ACTION
1 Ground (Y/B) wire at ECU with jumper wire and
Yes Check connection of ECU connector
check if MIL comes on
MTX e If OK, replace ECU w page F-149
I- i -!~ !r--~r’:~;-‘;- --~_:- ,
1 i r 1 1 1 ;-.:,~;~$~& {-; ,$&]j 4 If not OK, repair ECU connector
! No
Check if bulb is OK
ATX 13 If OK, repair (Y/B) wire between
ECU and instrument cluster
e If not OK, replace bulb CT page T-83
23UOFX-043
29 A/C DOES NOT WORK
DESCRIP- *Blower fan operates but magnet clutch does not operate
TION
[TROUBLESHOOTING HINTS]
*Open or short circuit in wiring harness
*A/C relay, A/C switch, or magnetic clutch malfunction
l ECU malfunction
TEP/ INSPECTION ACTION
1 1 Check ECU
terminal 10 (MTX) 10 (ATX) voltage 1
Yes Check ECU terminal 1 J (MTX) 1 L (ATX)
OK
CT= page F-152
MTX
T7J++!;i”-
L
ATX
No voltage OK
CT page F-152
1-3 If OK, check A/C system
c3- page U-30
~3 If not OK, replace ECU CT page F-149
Check for cause w page F-153
F-77