check engine MAZDA PROTEGE 1992 Repair Manual

F TROUBLESHOOTING GUIDE
14 IDLE MOVES UP AND DOWN/IDLE HUNTING
DESCRIP-
*Engine speeds up and down periodically at idle
TION
[TROUBLESHOOTING HINTS]
@ idle switch (built in throttle sensor) OFF at idle
@ Air leakage
@ Fuel injection amount inconstant
spoor contact point inside airflow meter
@ Poor ignition
iTEP INSPECTION
1 Check if “00” is displayed on Self-Diagnosis
Checker with ignition switch ON
CT page F-82
SYSTEM SELECT: 1
ACTION
Yes Go to next step
No
Service Code No. displayed
Check for cause (Refer to specified
check sequence) w page F-83
“88” flashes
,,;9 Check ECU terminal 1F voltage w page F-150
Specification: Battery voltage
(Ignition switch ON)
W: SELF TEST + If OK, replace ECU KIT page F-149
ELECT SW: A + If not OK, check wiring between
ECU and Self-Diagnosis Checker
2 Check for correct intake manifold vacuum 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 Check if air cleaner element is clean Yes Go to next step
w page F-79
No Replace air cleaner element
4
Disconnect high-tension lead at idle and check if Yes Go to next step
engine speed decreases equally at each cylinder
No Go to Step 9
5 Check if ECU terminal voltages are OK Yes Go to next step
w page F-150
No Check for cause KII page F-151
6
Connect System Selector to diagnosis connector Yes Go to next step
and set Test Switch to “SELF TEST” and check
for correct ignition timing at idle after warm-up
w page F-79
Ignition timing (BTDC)
l BP DOHC : 9”-11 o l BP SOHC : 4O-8” l B6 : 6O--8O No Adjust ignition timing r-7 page F-79
TEST SWITCH . .
F-52

TROUBLESHOOTING GUIDE F
No Replace airflow meter
9
Check for injector operating sound at idle Yes Go to Step 11
No Go to next Step
10 Check if battery voltage exists at injector connec- Yes Check if injector resistance is OK CT page F-131
tor (W/R) wire Resistance: 12-l 6fi
c3 If OK, check wiring between ECU
and injector
c3 If not OK, replace injector CT page F-131
No
Check wiring between ECU and injector
11 Check if strong blue spark is visible at discon-
Yes Go to next step
netted high-tension lead
No Check high-tension lead
+ If OK, check distributor cap and
rotor w page G-22
* If not OK, replace high-tension lead
12
Check if spark plugs are OK Yes Check for correct engine compression CT page Bl-10
w page G-16 82-10
Compression (Minimum):
. BP SOHC
834 kPa (8.5 kg/cm2, 121 psi)300 rpm
BON BUILDUP l BP DOHC
883 kPa (9.0 kg/cm*, 128 psi)-300 rpm
l.O-l.lmm ’ B6 DAMAGE AND 932 kPa (9.5 kg/cm’, 135 psi)-300 rpm DETERIORATION
c3 If OK, go to next step
c13 If not OK, check for cause CT page Bl-10
B2-10
No
Clean or replace w page G-18
13
Check for injector leakage Yes Replace injector CT page F-131
w page F-132
No Go
to next step
14 Try known good ECU and check if condition im-
proves cc7 page F-149
23UOFX-030
F-53

F TROUBLESHOOTING GUIDE
15
ENGINE STALLS ON DECELERATION
DESCRIP-
l Engine unexpectedly stops running while decelerating or after deceleration
TION l Idle condition normal
[TROUBLESHOOTING HINTS]
Engine speed drops too much when releasing accelerator or poor connector connection disconnected by deceleration
force
3 Idle speed control malfunction
3 Fuel cut control malfunction @ Idle speed misadjustment
TEP INSPECTION
ACTION
1
Check if idle condition is normal Yes
Go to next step
No Adjust or perform troubleshooting
Nos. 8-11 “ROUGH IDLE” v page F-42
F-48
--
2
Check if “00” is displayed on Self-Diagnosis Yes Go to next step
Checker with ignition switch ON
W page F-82 No
SYSTEM SELECT: 1 Service Code No. displayed
Check for cause (Refer to specified
check sequence) w page F-83
“88” flashes
Check ECU terminal IF voltage LIT= page F-150
Specification: Battery voltage
(Ignition switch ON)
W: SELF TEST + If OK, replace ECU w page F-149
Q If not OK, check wiring between
ECU and Self-Diagnosis Checker
3 Check switches for correct operation with Self-
Yes Go to next step
Diagnosis Checker Monitor Lamp with ignition
switch ON
w page F-105 No
Lamp not ON or OFF with specified
switch
Check for cause (Refer to specified
check sequence) CT page F-106
-,-y/
,’ Lamp always ON
Check wiring between ECU terminal 1 D
and Self-Diagnosis Checker
W: SELF
TEST
4 Check if ECU terminal voltages are OK
Yes Go to next step
MTX...Especially IV, 2D, 20, 2U, 2V and 2Q
ATX... Especially 28, 2E, 30, 3U, and 3V
w page F-150 No Check for cause w page F-151
5
Check for poor connection of following parts
Yes Repair or replace
. Ignition coil
l Igniter l Distributor
-- l High-tension lead
No l Injector Go to next step l Circuit opening relay l ECU
F-54

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
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

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
DAMAGE AND
DETERIORATION
Check if resistance of high-tension leads are OK Resistance: 16 kQ per 1 m (3.26 ft)
li;;g
‘&
d No
Replace
.
12 Check if resistance of ignition coil is OK Yes Go to next step c7 page G-19
Resistance (at 20°C [6SaF]):
Primary coil winding . . . . . . . . 0.61-0.99n
Secondary coil winding.... lo-16 kdl
PRIMARY COIL SECONDARY COIL
WINDING
WINDING
No
Replace
13 Check for correct engine compression Yes Go to next step u page Bl-10
92-10 No
Check engine condition ~7 page 81-10
Engine compression: 82-l 0
. BP DOHC
*Worn piston, piston rings or cylinder 663 kPa (9.0 kg/cm2, 126 psi)-300 rpm wall
l BP SOHC l Defective cylinder head gasket 634 kPa (6.5 kg/cm2, 121 psi)-300 rpm l Distorted cylinder head
l 66 l improper valve seating 932 kPa (9.5 kg/cm2, 136 psi)300 rpm *Valve sticking in guide
14 Change fuel and check if condition improves Yes Change fuel to another brand
No SOHC
Go to Step 16 DOHC
Go to next step
F-63

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
TEP INSPECTION ACTION
9 Check if airflow meter is OK Yes Go to next step
CT page F-168
I. Check if measuring plate moves smoothly
II. Check resistance No Repair or replace
Fc Ei Vc Ez Vs THA
WEAR AND CARBON BUILDUP
DAMAGE AND
DETERIORATION
Resistance (at 20% [68OF]):
Primary coil winding . . . . . . . . 0.81-0.99Q
Secondary coil winding.... IO-16 kQ
PRIMARY COIL SECONDARY COIL
cc;i’ page 81-10
Engine compression (Minimum):
883 kPa (9.0 kg/cm*, 128 psi)-300 rpm
834 kPa (8.5 kg/cm*, 121 psi)-300 rpm
932 kPa (9.5 kg/cm2, 135 psi)-300 rpm *Worn piston, piston rings or cylinder
l Defective cylinder head gasket l Distorted cylinder head
l improper valve seating
*Valve sticking in guide
F-67