1992 MAZDA PROTEGE Workshop Manual

TROUBLESHOOTING GUIDE F
TEP . INSPECTION
ACTION
6
Check if dashpot is correctly adjusted Yes Go to next step w page F-142
Dashpot set speed:
66
. . . . . . . . . . . . . . . . . ..*............ Approx. 3,000 rpm No Adjust dashpot w, page F-l 42
BP SOW . . . . . . . . . . . . . . . . . . . . . . Approx. 2,700 rpm
BP DOHC. . . . . . . . . . . . . . . . . . . . . . Approx. 3,500 rpm
7 Disconnect ISC valve connector at idle and
Yes Go to next step
check if engine speed increases CT- page F-l 16
No
Replace ISC valve w page F-109
6
Try known good ECU and check if condition
improves CT page F-149
23UOFX-03
F-45

TROUBLESHOOTING GUIDE
16 ENGINE STALLS SUDDENLY (INTERMITTENT)
DESCRIP- l Engine intermittently stops running
TION l Before stalling, engine condition OK [TROUBLESHOOTING HINTS]
@ Intermittently no spark or no-fuel injection caused by ve-
hicle vibration, acceleration, or deceleration
*Poor connection in wire harness
3 INSPECTION
Check if “00” is displayed on Self-Diagnosis
Checker with ignition switch ON c7 page F-82
g
-%ELECT SW: A
Check for poor connection of following parts l ignition coil
l igniter l Distributor l High-tension lead l lniector
l Ci;cuit opening relay l ECU
Check if ECU terminal voltages are OK
MTX...Especially lB, 2A, 28 and 2C
ATX... Especially lB, 3A, 38 and 3C w page F-150
Note
l When checking voltages, tap, move, and
wiggle harness and connector to recreate
problem
Yes
No Service Code No. displayed
Check for cause (Refer to specified
check sequence) Note
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 w page F-150
Specification: Battery voltage
(Ignition switch ON)
c3 If OK, replace ECU CT= page F-149
+ If not OK, check wiring between
ECU and Self-Diagnosis Checker
Yes
Repair or replace
No Go to next step
Yes
No
T ACTION
Go to next step w page F-83
Go to Troubleshooting No.2
‘CRANKS NORMALLY BUT WILL NOT
START (NO COMBUSTION)” CT- page F-30
Check for cause D page F-151
F-56

TROUBLESHOOTING GUIDE
17 HESITATES/STUMBLES ON ACCELERATION
bESCRIP-
*Flat spot occurs just after accelerator depressed or mild jerking occurs during acceleration
‘ION TROUBLESHOOTING HINTS]
0 Air/Fuel mixture becomes lean when depressing accelerator l Fuel injection control malfunction
(Correction for accelerating condition)
*Air leakage
l Fuel line pressure decreases l Spark advance control malfunction TEP INSPECTION ACTION
1 Check if “00” is displayed on Self-Diagnosis Yes Go to next step
Checker with ignition switch ON W page F-82 ’ No
Service Code No. displayed
SYSTEM SELECT: 1 Check for cause (Refer to specified
check sequence) w page F-83
“88” flashes
W: SELF TEST Check ECU terminal IF voltage CT= page F-150
Specification: Battery voltage
(Ignition switch ON) c3 If OK, replace ECU c? page F-149 * If not OK, check wiring between
ECU and Self-Diagnosis Checker Vacuum: More than 450 mmHg (17.7 InHg)
tern components
Replace air cleaner element 4
Check if ECU terminal voltages are OK
Yes Go to next step
MTX...Especiaily 2L
ATX... Especially lT, 2F, and 21 w page F-150
No Check for cause cp page F-151
5
Check if throttle linkage is correctly installed and
Yes Go to next step
operates freely w page F-l 14 ~~
Correct, clean, or replace as required
any binding or damaged linkage and
adjust cable deflection at throttle body w page F-l 14
6
Check continuity between throttle sensor termi- Yes Go to next step
nals IDL and E w page F-189
MTX
A-I-X 1
J E
IDL
Clearance between throttle
lever and stopper Continuity
MTX 0.1 mm (0.004 in) Yes
1 .Omm (0.039 in) No
ATX 0.1 mm (0.004 in)
Yes
0.6mm (0.024 in) No
No Adjust w page F-189
F-57

TROUBLESHOOTING GUIDE
TEP INSPECTION
ACTION
7 Check for correct fuel line pressure at idle Yes Check if fuel line pressure decreases w page F-129 when accelerating quickly Fuel line pressure:
c3 If decreases, check fuel line and fil- 265-314 kPa (2.7-3.2 kg/cm’, 38-46 psi) ter for clogging (Vacuum hose to pressure regulator dis- *
If no decrease, go to next step connected)
INSTALL CLAMPS No Low pressure
Check fuel line pressure while pinching
fuel return hose
+ If fuel line pressure quickly in-
creases, check pressure regulator w page F-129
+ If fuel line pressure gradually in-
creases, check for clogging be-
tween fuel pump and pressure
regulator
If not clogged, check fuel pump .*
maximum pressure w page F-126
8 Connect System Selector to diagnosis connector Yes Check if ignition timing advances when
and set Test Switch to “SELF TEST” and check accelerating
for correct ignition timing at idle after warm-up w page F-79
c3 If advances, go to next step
c3 If not advance, replace ECU w page F-149
Ignition timing (BTDC)
l BP DOHC : go-1 1 o l BP SOHC : 4’-8’
l B6 : 6O--8O No Adjust w page F-79
9
Check if air duct and air hoses are correctly Yes Go to next step
installed w page F-109
No
Repair
10 Check if exhaust system is restricted Yes Repair or replace w page F-136
No SOHC
Go to Step 12 DOHC
Go to next step
11 Check if variable inertia control system (VICS) is
Yes Go to next step
OK w page F-118
No
Repair or replace
12 Try known good ECU and check if condition
improves w page F-149
-’
F-58

TROUBLESHOOTING GUIDE
18 SURGES WHILE CRUISING
DESCRIP- *Unexpected change in engine speed which is usually repetitive
TION [TROUBLESHOOTING HINTS]
@ Air/Fuel mixture too lean
@ Misfire
3 Poor connection in wiring harness
SYSTEM SELECT:
1 “88” flashes
Check ECU terminal 1F voltage CT= page F-150
Specification: Battery voltage
(Ignition switch ON)
+ If OK, replace ECU w page F-149 4 If not OK, check wiring between
ECU and Self-Diagnosis Checker
check sequence) w page F-106
heck ECU terminal ID voltage CT page F-150
oxygen sensor
F-59

F TROUBLESHOOTING GUIDE
TEP INSPECTION ACTION
6 Check if throttle linkage is correctly installed and Yes Go to next step
operates freely
w page F-l 14
No Correct, clean, or replace as required
any binding or damaged linkage, and
adjust cable deflection at throttle body CT page F-l 12
7 Check for correct intake manifold vacuum at idle Yes Go to next step
Vacuum: More than 450 mmHg (17.7 intig) -
No
Check for air leakage of intake air sys-
tem components
8 Check if air cleaner element is clean Yes Go to next step
w page F-79
No Replace air cleaner element
9 Connect System Selector to diagnosis connector Yes Check if ignition timing advances when
and set Test Switch to “SELF TEST” and check accelerating
for correct ignition timing at idle after warm-up
w page F-79 c3 If advances, go to next step
c3 If not advance, replace ECU [II page F-149
Ignition timing (BTDC)
l BP DOHC : Q”-1 1 o l BP SOHC : 4O-6’
’ B6 : 6O-8O
No Adjust CT+ page F-79
10 Check for correct fuel line pressure at idle Yes Check if fuel line pressure decreases
w page F-129 when accelerating quickly
Fuel line pressure: c3 If decreases, check for fuel pump
265-314 kPa (2.7-3.2 kg/cm*, 38-46 psi) maximum pressure w page F-126
(Vacuum hose to pressure regulator dis- If OK, check fuel line and filter for
connected) clogging CI,’ page F-122
+ If no decrease, go to next step
-
No Low pressure
Check fuel line pressure by pinching
fuel return hose
cti If fuel line pressure quickly In-
creases, check pressure regulator CT page F-129
ti If fuel line pressure gradually in-
creases, check for clogging be-
tween fuel pump and pressure
regulator
If not clogged, check fuel pump
maximum pressure cr page F-126
-
High pressure
Check if fuel return line is clogged
Q If OK, replace pressure regulator C-Y- page F-130
+ If not OK, replace
--_I. 1”1-~~-~~
11 Check if exhaust system is restricted Yes Repair or replace
C-T- page F-136
No Go to next step
12 Try known good ECU and check if condition
improves
CT page F-149
23UOFX-034
F-60

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

F TROUBLESHOOTING GUIDE
ITEP
INSPECTION ACTION
6 Check for correct intake manifold vacuum at idle Yes Go to next step
Intake manifold vacuum:
More than 450 mmHg (17.7 inHg) No Check for air leakage of intake air sys-
tem components
7 Check if air cleaner element is clean Yes Go to next step
w page F-79
No Replace air cleaner element
8 Check for correct fuel line pressure at idle Yes Check if fuel line pressure decreases
CT= page F-129 when accelerating quickly
Fuel line pressure: c3 If decreases, check fuel pump
265-314 kPa (2.7-3.2 kg/cm’, 38-46 psi) maximum pressure w page F-126
(Vacuum hose to pressure regulator dis- If OK, check fuel line and filter for
connected) clogging
ti If not decrease, go to next step
No Low pressure
INSTALL CLAMPS Check fuel line pressure while pinching
fuel return hose
9 If fuel line pressure quickly in-
creases, check pressure regulator w page F-129
c3 If fuel line pressure gradually in-
creases, check for clogging be-
tween fuel pump and pressure
regulator
If not clogged, check fuel pump
maximum pressure w page F-126
High pressure
Check if fuel return line is clogged
c3 If OK, replace pressure regulator CT page F-130
d If not OK, replace
9 Check if airflow meter is OK
Yes Go to next step
w page F-188
I. Check if measurin late moves smoothly
II. Check resistance No Repair or replace
F-62