1989 MAZDA 323 section E

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

F SELF-DIAGNOSIS FUNCTION
Troubleshooting
If a service code number is shown on the SST, check for the cause by using the chart related to the code
number shown.
Service code number
CODE LOCATION OF
NO.
MALFUNCTION OUTPUT SIGNAL PATTERN
SELF-DIAGNOSIS FAIL-SAFE
02
Ne-signal
:E nl-u No Ne-signal
-
03 G-signal
(DOHC) No G-signal Cancels 2-group
injection
06* Vehicle speed
sensor ON
OFF No input signal from Shifting performed
vehicle speed normally
sensor
08 Airflow meter ON
OFF Open or short circuit Basic fuel injection
amount fixed as for two
driving modes
(1) Idle switch ON
(2) Idle switch OFF
09 Water
thermosensor ON
OFF Maintains constant 20%
(68OF) command
10 Intake air
thermosensor Maintains constant 20°C
(68OF) command
12
Throttle sensor
“,E l--uL-l Throttle opening judged
as full stroke lockup not
provided
Atmospheric ON Maintains constant
14 pressure sensor command of sea level
(in ECU)
OFF pressure
15 Oxygen sensor
(inactivation) ON
OFF Sensor output
continues less than
0.55V 95 sec. after
engine starts
(1500 rpm) Cancels engine feedback
operation
Oxygen sensor ON Sensor output Cancels engine feedback
17
(Inversion) continues uncharged operatron
OFF 50 sec. after engine
exceeds 1500 rpm
Solenoid valve ON
25 (pressure
regulator)
OFF u 1 nnluln Open or short crrcurt
“If the marked code numbers appeor, refer to Section K
F-84

SELF-DIAGNOSIS FUNCTION F
:ODE LOCATION OF
NO.
MALFUNCTION
26 Solenoid valve ON
(purge control)
OFF OUTPUT SIGNAL PATTERN nnnnnll 1 SELF4IAGNOSIS
Open or
short circuit FAIL-SAFE
-
ON
34
ISC valve
OFF u 1 llllJlll r -
41 Solenoid valve ON
(WCS)
[DOHC]
OFF -
Pulse ON No input signal Shifting performed in
55*
i nnnnn
from pulse accordance with signals
generator
OFF generator from vehicle speed
sensor
Open or Solenoid valve(s)
60* 1-2 shift ON
short circuit
solenoid valve
uuuuul performs the shifting with
as little interference as
OFF
possible with driving
performance
2-3 shift ON Lockup not provided
61*
solenoid valve
OFF
UUUI n
3-4 shift ON
62’
solenoid valve
OFF u u u u inn
1.6 sec. 4 sec.
63* Lockup solenoid
valve
u u&m I- Shifting performed
normally
Lockup not provided
0.4 sec.
0.4 sec.
*If the marked code numbers appeor, refer to Section K
Note
l The HOLD indicator does not flash the service code numbers.
l If there is more than one failure present, the code numbers will be indicated in numerical or-
der, lowest number first.
* After repairing a problem, turn the ignition switch OFF and disconnect the negative battery
cable at least 20 seconds to erase the service code numbers from the engine control unit (ECU)
memory.
23UOFX-051
F-85

SELF-DIAGNOSIS FUNCTION
Inspection Procedure
1. Connect the SST (System Selector) to the diagnosis con-
nector.
2. Set the switch @ to position 1.
3. Set TEST SW to SELF-TEST.
03UOFX.090
MONITOR LAMP
T
03UOFX-091
Procedure
4. Connect the SST (Self-Diagnosis Checker) to the System
Selector and a ground.
5. Set the select switch of the Self-Diagnosis Checker to posi-
tion A.
6. Turn the ignition switch ON.
7. Check if Monitor Lamp illuminates when each switch is made
to function as described below.
Caution
* If either of the switches remain activated, the mon-
itor lamp will be illuminated.
l Do not start the engine.
I
I Set conditions to deactivate each switch l All accessories OFF l Transaxle in neutral l All pedals released NO
-
Verify that monitor lamp does not illuminate
YES
Check each switch as described Check each switch and related wire harness
*Clutch and Neutral CT- pages F-l 72,173
switch
*Throttle sensor w page F-169 l Stoplight switch c7 Section T l Headlight switch c7 Section T l Rear defroster switch T;P Section T l Blower switch [r+ Section T
l Inhibitor switch a Section K l A/C switch 0 Section U l Water thermoswitch c7 Section E
23UOFX-OS!
Neutral and Clutch switch (MTX)
Shift transaxle into gear
Check that monitor lamp illuminates with clutch pedal
released
YES NO PC: l Neutral switch malfunction a page F-173 l Clutch switch malfunction w page F-172
*Open circuit in related wire
harness
l ECU terminal 1 V voltage
incorrect w page F-152
l ECU malfunction
Depress clutch pedal
Check that monitor lamp does not illuminate
Return transmission to neutral PC:
*Clutch switch malfunction w page F-172
23UOFX-088
F-l 06

SELF-DIAGNOSIS FUNCTION
Headlight switch
Turn headlight switch ON
Check that monitor lamp illuminates
YES
Headlight switch OK
Turn headlight switch OFF NO
PC: l Headlight switch malfunction v Section T
*Open circuit in wire harness
from headlight switch to ECU
l ECU terminal 1 U (MTX) 1 H
(ATX) voltage incorrect CT page F-152
l ECU malfunction
23UOFX-087
Rear window defroster switch
Turn rear window defroster switch ON
Check that monitor lamp illuminates
YES
Rear defroster switch OK
Turn rear window defroster switch OFF NO
_ PC: *Rear window defroster switch
malfunction c7 Section T
*Open circuit in wire harness
from rear window defroster
switch to ECU
l ECU terminal 1 T (MTX) 1 J (ATX)
voltage incorrect
u page F-152
l ECU malfunction
23UOFX-088
Inhibitor switch (ATX)
Shift transaxle into L, S, D, or P range
Check that monitor lamp illuminates
YES
Inhibitor switch OK
Shift into P or N range PC: l Inhibitor switch malfunction
*Open or short circuit in related
23UOFX-089
F-l 07

SELF-DIAGNOSIS FUNCTION
Throttle sensor
Depress accelerator pedal (not fully) and check that
monitor lamp illuminates
YES NO
PC: *Throttle sensor malfunction CT page F-169
*Short circuit in wire harness
from throttle sensor to ECU
*ECU terminal 1 N (MTX) 1T
(ATX) voltage incorrect CT page F-150
l ECU malfunction
Depress acceleration pedal fully and check that monitor
No : PC: *Throttle sensor malfunction w page F-169
lamp does not illuminate *Open circuit in wire harness
from throttle sensor to ECU
YES *ECU terminal 2L (MTX) or 21
(ATX) voltage incorrect a page F-154
Throttle sensor OK
Release accelerator pedal
23UOFX-090
Stoplight switch
Depress brake pedal
Check that monitor lamp illuminates
YES
Stoplight switch OK
Release brake pedal NO
PC: *Stoplight switch malfunction w Section T
*Open circuit in wire harness
1
from stoplight switch to ECU
*ECU terminal 10 (MTX) 1Q
(ATX) voltage incorrect CT page F-l 52
l ECU malfunction
23UOFX-091
Blower switch
---
Turn blower switch to 2nd or higher position
Check that monitor lamp illuminates
YES
Blower switch OK NO
__L PC: *Blower switch malfunction
*Open circuit in wire harness
from blower switch to ECU
l ECU terminal 1 S (MTX) 1 P
(ATX) voltage incorrect
l ECU malfunction p Section T
w page F-152
23UOFX-092
F-l 08