1992 MAZDA 323 check engine

TROUBLESHOOTING GUlbE F3 1
14 IDLE MOVES UP AND DOWN/IDLE HUNTS
IESCRLP-
l Engine speeds up and down periodically at idle
UON
TROUBLESHOOTING HINTS]
B Idle switch (En throttle sensor) OFF at idle
3 Air leakage
3 Fuel injection amount Inconstant
. Poor contact point inside airflow meter
9 Poor ignitron
rEP[ INSPECTION
I is “00” displayed on Self-Dragnosis Checker
with ignrtron swatch ON?
SYSTEM SELECT: i I ACTfON
Yes Go to next step
NO Service Code No. displayed
Check for cause (Refer to specified
check sequence) c=;r page F3-16
“86” flashes

Check ECU terminal IF vottage csr page F345
Voltage: Battery voltage
W: SELF TEST (ignition switch ON)
SELECT SW: A
.d P/ e If OK, replace ECU CT page F3-3
c3 If not OK, check wrrjng
(ECU - Self-Dlagnosls Checker)
2 Is intake manrfold vacuum correct at idle? Yes Go to next step
Intake manifold vacuum:
More than 450 mmHg { 17.7 inHg )
No Low vacuum
Check for air leakage at intake air
system
3 Is air cleaner element clean? Yes Go to next step
No Replace abr cleaner element
4 Disconnect each hrgh-tension lead at idie; does Yes Go to next step
engine speed decrease equally at each cylinder?
No Go to Step 8
5 Are ECU terminal voltages OK? Yes Go to next step
(especially 20, 2Q, 20) -
rI7 page F345 No
Check for cause
6 Connect System Selector to diagnosis connector Yes Go to next step
and set Test Switch to SELF TEST; is ignition
timing at idle correct after warm-up?
Ignition timing (BTDC): f 0 f la
No Adjust ignition timing
._
. F3-33

TROUBLESHOOTING GUIDE
(at 20% [SS*F])
If It is, check wiring
e If OK, check distributor cap and
rotor
e If not OK, replace high-tensjon lead
12 Are spark plugs UK? Yes Is engine compresston correct? w Section 82
w Section G
. Wear and carbon burld up Engine compression: l Plug gap 1059 kPa 110.8 kgf/cm*, 352 psi I-300 rpm l Damage
4 If OK, go to next step
4 If not OK, check for cause
w Section 82
c
NO Clean, adjust
13 Check for injector leakage Yes
Replace injector
No Go to next step
14 Try known good ECU: does condition improve?
w page F3-45
----- Am.*
F3-34
~ROlJ8L Engine so:
3 Idle-sp.
T> fuel-cL

TROUBLESHOOTING GUiDE F3
15 ENGINE STALLS ON DECELERATION
IESCRIP-
l Engrne unexpectedly stops running dunng or after deceleration
[iON l Idle condition normal.
TROUBLESHOOT1NG HtNTS]
ingrne speed drops too much when releasrng accelerator
3 Idle-speed misadjustment @I Loose connector disconnected by force of deceleration
3 Fuel-cut contrd malfunction
TEP lNSPECTlON ACTION
1 1s idle condition normal? Yes Go to next step
tdle speed: 800 f 50 rpm (in neutral)
NO Adjust or perform Troubleshooting, Nos.
8-I 1 “ROUGH IDLE”
(Refer to Workshop Manual
(1203-I o-89F))
2 Is “00” displayed on Self-Diagnosis Checker Yes Go to next step
with ignition switch ON?
SYSTEM SELECT: 1 NO Service Code No. displayed
Check for cause (Refer to specified
check sequence) ET page F3-16
“88” flashes
Check ECU termrnal 1 F voltage
Voltage: Battery voltage
(ignition switch ON) r;r page F346
W:SELFTEST
e If OK, replace ECU CI page F3-3
4 If not OK, check wirtng
(ECU - Self-Diagnosis Checker)
3 Does Self-Diagnosis Checker Monitor Lamp with Yes Go to next step
lgnttlon switch UN show that switches operate
correctly?
NO Lamp not ON or OFF with specified
switch
Check for cause (Refer to specified
check sequence)
W: SEtF TEST Lamp slways ON
Check wiring between
(ECU terminal 1 D - Self-Diagnosis
Checker)
4 Are ECU ?erminal voltages OK? Yes Go to next step
(especially IV, 20, 20, ZU, 2V.
and 20) v page F346 No
Check for cause
5 Check for poor connection of foltowing parts YC?S Repair or replace
l ignrtion coil l Igniter l Olstribdor l High-tension lead
NO Go to next step l Injector. l Injector resistor l Ctrcuit-opening relay . l ECU
F3-35

F3 TROUBLESHOOTING GUIDE
STEP INSPECTION ACTlON
6 Is dashpot correctly adjusted? Yes Go to next step
c
Dashpot set speed: Approx. 3,500 rpm
No Adjust dashpot
7
Try known good ECU; does condition
Improve?
w page F3-3
13EOF3-336
16 ENGINE STALLS SUDDENLY (INTERMITTENT)
DESCRIP.
l Engine intermittently stops running
TION l Before stalling, engine conditron is OK
TROUBLESHOOTING HINTS]
@ intermittently no spark or no fuel injection caused by ve-
hlcle vibratron, acceleratton, or deceleration
l Poor connectlon in wiring harness
iTEP INSPECTION ACTfON
1 Is “00” displayed on Self-Oiagnoss Checker Yes Go to next step
with lgnltlon swrtch ON?
NO Service Code No. displayed
Check for cause (Refer to speclfled
check sequence).
Note CT page F3-16
l When checking wiring harness and
connectors, tap, move, and wiggle
suspect sensor and/or harness to
recreate problem
“88” flashes ’
Check ECU terminal IF voltage
Voltage: Battery voltage
{ignition swttch ON) w page F3-45
4 If OK, replace ECU
4 If not OK, check wiring
(ECU - Self-Diagnosis Checker)
2 Check for poor connection of foliowrng parts
Yes Reparr or replace
l lgnltfon coil l Igniter l Distributor l t-flgh-tensron lead
No Go to next step l Injector l Injector reststor l Circutt-opening relay l ECU
3 Are ECU terminal voltages OK? Yes Go to Troubleshbotrng No. 2
(especially 16, 2A, 2B, and 2C) .“CRANKS NORMALLY BUT WILL NOT
w page F3-45 START (NO COMBUSTION)”
w page F3-20
Note
. No Check for cause
l When. checking voltages, tap, move, and
wiggle harness and connector to recreate
problem
* lrlrl m-7
F3-36
7.8-l

FUEL SYSTEM F3
13EOF3.34
c I 13EOF3-364 FUEL PUMP CONNECTOR
/
!NSTALL CLAMPS
I
l nspection
1, Disconnect the resistor/relay connector.
2. Ground the fuel pump resistor relay terminal D.
3. Apply battery voltage and check for continuity as shown.
Terminal C
Continuity between A and I3
Battery voltage applied NO
ov Yes
4. Measure the resistance between terminals E and F.
Resistance : 0.38--0.42Q (at 2O*C {6S°F 1)
PRESSURE REGULATOR
Inspection
Fuel line pressure
Warning
l Before performing the following operation, release
the fuel pressure from the fuel system to reduce the
possibility of injury or fire. (Refer to page F3-21.)
1. Disconnect the negative battery terminal.
2. Connect a fuel pressure gauge between the fuel filter and
the fuel main hose. (install clamps as shown.) , .
I
3. Connect the negative battery terminal.
/t.
4, Start the engine and run it at idle.
5. Measure the fuel line pressure.
Fuel line pressure:
206-255 kPa [ 2.1-2.6 kgflcml, 30-37 psi )
6. Disconnect the upper vacuum hose from the pressure regu-
lator and measure the fuel line pressure.
Fuel line pressure:
304-392 kPa (3.1-4.0 kgf/cm2, 44-57 psi )
F3-41

. !I11
PRESSURE REGULATOR CONTROL SYSTEM F3
13EOF3353
(PRC HIGH TEMP.)
13EOF3-35:
BAl-fERY VOLTA
PRESSURE REGULATOR CONTROL
SYSTEM
SOLENOID VALVE (PRESSURE REGULATOR CONTROL)
Inspection
On-vehicte
1. Start the engine and run it at idle (cold engine).
2. Disconnect the vacuum hoses from the pressure regulator,
and verify that vacuum is felt at each hose.
3. Ground the solenoid valve terminal wire (G/O...low temp.
and G. ..high temp.) by using a jumper wire, and verify that
no vacuum is felt.
4. If vacuum is not as specified, check the solenoid valve.
Solenoid Valve (high and low temp.)
1, Disconnect the vacuum hose from the solenoid valve and
the vacuum pipe..
2. Blow through the solenoid valve from port A.
3. Verify that air flows from port B.
4. Disconnect the solenoid valve connector.
5. Connect battery voltage and a ground to the terminals of
the solenoid v&e.
6. Blow through the solenoid valve from port A.
7. Verify that air flows from the valve air filter.
8. If not as specified, replace the solenoid valve.
.
F3-43

CONTROL SYSTEM F3
hT==TdI ,
USE CONNECTOR A 1
L
93GOF3-787 ENGINE CONTROL UNIT (ECU)
Inspection
1. Disconnect the ECU connectors.
2. Connect the SSTs {Engine Signat Monitor and Adapter) to
the ECU as shown.
3. Place the SST (Sheet) on the Engine Signal Monitor.
4. Measure the voltage at each terminal.
(Refer to pages F3-46 to F3-53.)
5. If any ECU terminal voltage is incorrect, check the related
input or output devices and wiring. If no problem is found,
replace the ECU. (Refer to page F3-2.)
t
1 13EOF3-358
r
TERMINALS
f. -I AANDB . Caution l Never apply voltage t.o terminals A and 8 of the SST.
! :OF3-359
F3-45

F3 CONTROL SYSTEM
Terminal voltage
Reference date
Vs: Battery voltage
‘em&al Input Output Connected to Test condition Correct voltage Remark
1A - - Battery Constant VB
For backup
18 0 Main relay
Ignition switch OFF ov
(FUEL INJ relay) -
ON
V8
1C 0 lgnitlon switch While cranking Approx. 1 OV
(START) -
Ignition switch ON ov
10 0 Self-Diagnosis Test switch at SELF TEST
Wtth Self-
Checker Lamp illuminated for 3 sec. after ignition Approx. 5V
(monitor lamp) switch OFFdON Diagnosis Check-
er and System
lamp not iltuminated after 3 sec. V8 Selector
Test switch at 02 MONITOR with engine
idling Approx. 5V
Monitor lamp illuminated
Test switch at 02 MONITOR with engine
idling Vi3
Monitor lamp not illuminated
IE - - - - - -
IF
0 Self-Diagnosis Buzzer sounded for 3 sec. after ignition
Below 2SV
l With Seif-
Checker switch OFF-+ON
Diagnosis
(service code)
Buzzer not sounded after 3 set V0 ’ Checker and
Buzzer sounded Below 2.5V System Selector
l With System
Buzzer not sounded VB Selector test
switch at SELF
TEST
1G 0 igniter tgnition switch ON
ov
-
Idte
Approx. 0.2V
It-l 0
Solenoid valve Ignition switch ON
VB
(wastegate)
Idle
Approx. 2V ’ -
II
0 Fuel pump While cranking
Approx. 1 OV
resistor/relay -
Idle
8etow 1.5V
IJ 0 NC relay Ignition switch ON
VB
A/C switch UN at idle
Below 2.5V
. NC switch OFF at idle V3
-
IK 0 Diagnosis
connector
(TEN terminal) System Selector test switch at
02 MONITOR
System Selector test switch at
SELF TEST V0
-
8elow l*OV
1L - - - - - -
I
1M - - - - -
I -
lr ‘- l-7
f L.-
r
20 20 2M 2K 21 2G 2E 2c 2A IU 1S 10 10 ltvl tK II Ir; tE 1~ IA
1
22 2x 2v 2T ZR 2P 2N 2L 25 2H 2F 20 2B 1V IT 1R tP 1N IL 1J 1H IF 1~ 1~
1
J=3-46 --
4lways 4
--
AIways 4
--
Atways 1
--
Always 1
-a
Always ’
--
Always i
-e
Always I
2.5v
Always
Always (
-m
Always f
-a
Always 1
Always (
--
Always I
2.5V
Always 1
Always t
Always
--