1990 MAZDA 232 engine

F2 TROUBLESHOOT1NG GUIDE
25 HIGH OIL CONSUMPTION [BP TURBO]
DESCRIP- 1
l Oil consumption excessive
TION l Exhaust gas white
TROUBLESHOOTING HINTS1
a PCV system malfunctton *
@ Englne malfunction (Oil
working up, working down, or leakage)
3 Oil leakage from turbocharger
ZEP [ INSPECTION Repair or
replace 1 Check if PCV hose, ventilation hose or their at-
taching nipples are separated, damaged,
ciogged, or restricted 2
Check insrde of air hose, air pipe, and intercool-
er for excesstve oil
3 1 Check white exhaust gas visible when ventilation
1 hose or PCV hose removed
1
4 Remove turbocharger and check at oil seals of
compressor and turbine shafi for oil leakage Yes
NO Yes
NO Yes
No Check hoses for clogged
Yes Replace turbocharger
NO
ACTION
Go to next step
Possibly oil working up
Check PCV valve and PCV hose for
clogged
+ If OK, go to next step
e If not UK, repalr or replace
Go to next step
Go to next step
Engine malfunction (Oil working up,
working down, or leakage)
Check foltowing
. Worn piston or cyiinder
l Worn piston ring groove’ l Stuck piston rings* l Worn vatve seal* l Worn valve stem * l Worn vatve guide’
* Refer to 323 Workshop Manual [1203-IO-89F (Europe) or 1204-IO-89F (Australra)].
93GOF2-74:
FZ-42

TURBOCHARGER CONTROL SYSTEM F2
TURBOCHARGER CONTROL SYSTEM
PREPARATION
SST
49 HO80 740
Gauge. pressure
I 93GOF2-754
93GOF2-755
L I 93GOF2-756
93GOF2-757 93GOF2-753
SYSTEM OPERATION
1. Install a pressure gauge 149 kPa (0.5 kg/cm2, 7.1 psi)
min.1.
2. Connect a tachometer to the diagnosis connector lG-
terminal.
3. Start the engine.
4. Verify that the boost pressure when the engine speed is
4,000 rpm is within specification.
Specification: More than 2.0 kPa ( 0.02 kg/cm2, 0.3 psi)
5. If not within the specification, check for air Ieakage, exhaust
gas leakage, and for the wastegate stuck open.
6. if OK, replace the turbocharger.
WASTEGATE
Inspection
1. Remove the air hose from the wastegate actuator.
2 Connect the SST to the actuator.
3. Raise the front of the vehicle and support it on safety stands.
4. Remove the undercover.
F2-45

F2 TURBOCHARGER CONTROL SYSTEM
I 93GOF2-756
93GOF2-75!
93GOF2-761
5. Mark the actuator rod.
Caution
l Do not apply compressed air over 98 kPa (1.0
kg/cm2, 14 psi).
6. Adjust the compressed air pressure to 83 kPa (0.85
kg/cm”, 12 psi).
7. Verify that the rod moves when applying and releasing air
pressure.
WASTEGATE SOLENOID VALVE
Inspection
1, Remove the ,solenoid valve.
2. Verify that air does nut flow from @ through @
3. Apply IN to the solenoid valve and verify that air flows from
@ through @
TURBUCHARGEFI
Inspection
1. Be sure tf7e engine is cool.
2. Remove the air hose.
3. Check that the compressor wheel assembly turns smoothly.
4. If there is excessive drag or noise, replace the turbocharger.
93GOF2-761
FZ-46

TURSUCHARGER CONTROL SYSTEM F2
Removal I InstaIlation
Caution
l Be carefui of following points after turbocharger removal.
l Do not carry the turbocharger by the actuator rod or actuator hose.
l Do not drop the turbocharger.
l Set the turbocharger down with the turbine shaft horizontal.
9 Cover the intake, exhaust, and oil passages to prevent dirt or other materia1 from entering.
l Use the specified new studs when installing the turbocharger.
1. Disconnect the negative battery cable.
2. Lift up the vehicle.
3.
Remove the undercover.
4. Drain
the engine coolant.
5. Remove in
the order shown in the figure.
6. fnstall in the reverse order of removat, referring to Installation Note.
7.8-l 1 N-m (80-l 10 cm-kg, 69-95 in-lb)
G I’
/
43-61 (4.4-6.2, 3245)
36-42 (3.94.3, 28-
7.8-1 1 N-m (80-110 cm-kg, 6
cm-kg, 69-95
indb)
26-31
12.7~g-2. 20-231
w
19-26 (l-9-2.6, 14-19)
7.6-17 N-m (80-7 t d cm-kg, 69-95 in-lb)
N-m (m-kg, Mb]
I 93GOF2-762
F2-47

F2 TURBOCHARGERCONTROLSYSTEM
1. Radiator
2. Insulators
3.
Air hose, and air pipe
4. Oxygen
sensur connector
5. Front exhaust pipe
6. Bracket
1 I 93GOF2-765
93GOF2-761
7. Water hoses
8. Oil pipe
9. Oil return pipe
10. Exhaust
manifold and turbocharger
Removal Note . . . . . . . . . . . . . . . . . . . . . . .._.-........_ below
Installation Note . . . . ..__-.............._...___.._. below
93GOF2-763
Removal Note
Exhaust manifold and turbocharger
1. Remove the exhaust manifold and the turbocharger as an
assembly .
2. Remove the turbocharger from the exhaust
manifold.
InstaIlation Note
Exhaust manifold and turbocharger
1. Remove all gaskets and sealant.
2. Install new gaskets.
3. Supply 25 cc (1.5 cu in) of oil through the oil passage of
the turbocharger.
4. Install the turbocharger to the exhaust manifold.
5. Install the turbocharger and the exhaust manifold assem-
bly to the engine and loosely tighten the nuts.
6. install the bracket and the front exhaust pipe, and tighten
the turbocharger mounting nuts.
AIR BYPASS VALVE
Removal I Installation
1. Remove the vacuum hose and the air hoses from the air
bypass valve.
2. Remove the air bypass valve.
3. Install in the reverse order of removal.
Inspection
1. C_onnect a vacuum pump to air bypass valve port @-
2. Verify that air flows from port @through port @ when 250
f 35 mmHg (9.8 * 1.4 inHg) vacuum
is applied to port
0 a .

F2 FUEL SYSTEM
FUEL
SYSTEM
PREPARATlON
SST
49 LO18 901
Injector checker For
lnsgectlon of
injector
93GOF2.770
9MUOF2-722
03UOFX-7 27
F2-50
PRECAUTION
Fuel Pressure
Release and Servicing Fuel System
Fuel in the fuel system remains under high pressure when the
engine is not running.
a) Before disconnecting any fuel line, release the fuel pres-
sure from the fuel system to reduce the possibility of injury
‘or fife,
1. Start the engine.
2. Push the rear seat cushion buttons and remove the
cushion,
3. Disconnect the fuel pump connector.
4. After the engine stalts, turn off the ignition switch.
5. Recpnnect the fuel pump connector and install the rear
seat cushion.
b) Use a rag as protection from fuel spray when disconnect-
ing the hoses.
Plug the hoses after
removal.
c) When inspecting the fuel system, use a suitable fuel pres-
sure gauge.
Caution
l Install hose clamps to secure the fuel pressure
gauge to the fuel filter and the fuel main hose to pre-
vent fuet leakage.
Priming Fuel System
After releasing the fuel pressure for repairs or inspection, the
system must be primed to avoid excessive cranking when first
starting the engine. Follow the steps
below.
1. Connect the diagnosis connector terminals F/P and GND
with a jumper wire.
2. Turn the ignition switch
ON for approx. 10 set, and check
for fuel leaks.
3. Turn the ignition switch OFF and remove the jumper wire.

CONTROL SYSTEM F2
CONTROLSYSTEM
PREPARATION
SST
49 HOt8 9A3
Self-dragnosls
checker
Engrne signal
IT-iOFlllO~ 49 GO18 904
Sheet System selector
I 93GUF2-786
For inspection of ECU
93GOF2-787
93GOF2-801
TERMNALS 1
--I”- -
03UOFX
ENGINE CONTROL UNIT (ECU)
Inspection
1. Disconnect the ECU connectors.
2. Connect the SSTs (Engine Signal Monitor and Adapt-
er) to the ECU as shown.
3. Place
the SST (Sheet) 011 the Engine Signal Monitor.
4. Measure the voltage at each terminal.
(Refer to pages FZ-60 to F2-67.)
5. If any ECU terminal voltage is incorrect, check the related
input or output devices and wiring. If no problem is found,
reptace the ECU. (Refer to above.)
Caution l
Never apply voltage to SST terminals A and B.
F2-59

F2 CONTROL SYSTEM
Terminal voltage [BP TURBO]
eminal input Output , 1 Connected to Test condition Correct voltage Remark
IA - - Battery Constant Approx. 12V for backup
15 0 Main relay OFF Approx. OV
(FUEL INJ relay) tgnltlon switch
-
ON Approx. 12V
1c 0 1 Ignition switch Wniie cranking Approx. 1 OV
-
(START)
lgnrtron switch ON Approx. OV
ID 0 Self -Diagnosis Test switch at “SELF-TEST” With Self-
Checker Lamp illuminated ior 3 sec. after ignition Approx. 5V Diagnosis Check-
(Monitor lamp) switch OFF* ON er and System
Lamp not illuminated after 3 sec. Approx. 12V Se’ector
Test switch at
“02 MONITOR” at idle
Monitor lamp illuminated Approx. 5V
Test switch at
“02 MONITOR” at idle
Monitor lamp not illumrnated Approx. 12’4
-lE - - - -
- -
1F 0 Self-Diagnosis Buzzer sounded for 3 sec. after ignition
Below 2.5V l With Self-
Checker switch OFF -+ ON Diagnosis
(Code Number)
Buzzer not sounded after 3 sec. Approx. 12V Checker and
Buzzer sounded Below 2.9 System Selector
l With System
Buzzer not sounded Approx. 12V Selector test
switch at
“SELF-TEST’ ’
I I 1G
0 Igniter
7H
0 Solenoid vahe
(Wastegate)
l!
0 Fuel pump
resistor/relay
I
lJ I r-Tcreiay Ignition switch ON
ld!e
Engine speed below 5,300 rpm
Engine speed above 5,300 rpm
While cranking
Idle
Ignition switch ON
AK switch ON at idle 1 Approx. OV
-
Approx. 0.2V
Approx. 12V
-
Below 1.5V
Approx. 1 OV
-
I3elow 15V
Approx. 12V
Below 2.5V
AIC switch OFF at idle Approx. 12V
-
IK 0 Diagnosis System Selector test switch at
connector
(TEN terminal)
1L - - -
- -
-
IM
t 0
1 Ground (Australia) Constant Below 1 .OV Not used
(Except Australia)
F2-60