1990 MAZDA 232 fuel pressure

TROUBLESHOOTING GUIDE F2
]sTFP 1 INSPECTION ACTION
I
Aerator depressed ful ty
rminal 1F voltage
: SELF TEST
ignition timing: BTDC 10 = I*
8 Check for correct fuel line pressure at idle’ Yes Check if fuel line pressure decreases
when accelerating quickly
Fuel line
pressure: 265-314 kPa (2.7-3.2 kg/cm’, 38-46 psi)
(vacuum hose to pressure regulator dis-
connected) 4 If decreases check fuel pump
maximum pressure*
If OK, check fuel line and filter for
clogging
4 If no decrease, go to next step
NO Low pressure
Check fuel irne pressure while pinching
fuel return hose
4 If fuel line pressure quickly in-
creases, check pressure
regulator' e If fuel lrne pressure gradually in-
creases, check for cloggrng be-
tween fuel pump and pressure
regulator
If not clogged, check fuel pump
maximum pressure* High pressure
Check of fuel return line is ctogged
4 If OK, replace pressure regulator
e If not OK. replace
- _
* Refer to 323 Workshop Manual
[I 203-1 O-89F (Europe), or 1204-lU-89F (Australra)].
FZ-33

F2 TROUBLESHOOTING GUIDE
20 POOR ACCELERATION [BP TURBO]
IESCRIP- . Performance poor while accelerating
rm
l Idle condition normal
[TROUBLESHOOTING HINTS]
3 Wastegate always open or opens early @ Low intake air amount
3 Turbocharger damage
l Throttle valve not open fully
3 Factors other than engine malfunction *Clogged intake air system l
Ciutch slIpping @ Air/Fuel mixture Iean l Brake draggrng l fuel line pressure decreases
l low tire pressure l Fuel Injection malfunction
l Incorrect tire size @ Poor Ignition
. Overloaded vehicle @ Low engine compression
@ Atcohol blended fuel used
TEP INSPECTION ACTION
-l Install pressure gauge
in intake air pipe and I Yes
1 Go to Step 3
check boost pressure at engine speed of 4,000
rpm
w page F2-45
Boost pressure:
More than 2.0 kPa (0.02 kglcm2, 0.3 psi)
No Check for air leakage and exhaust gas
leakage
4 If OK, go to next step
4 If not OK, repair
2 Check wastegate w page F2-45
Yes Remove Intake air pipe from turbo-
charger and check if compressor wheel
rotates smoothly w page F2-46
c3 If OK, check air cleaner element
and throttle valve
4 If not ok, replace turbocharger
3 Check factors
other than engine
Yes Go to next step l Clutch stipprng l 5rake dragging l Low tire pressure
No l Incorrect ttre size Repair or adjust
FZ-36

F2 TROUBLESHUOTtNG GUIDE
check fuel pump maxi-
fuel line and filter for
pump and pressure
High pressure
Check if fuel line is clogged
II. Measure resistance
r--- ---_--es-,
DAMAGE AND
DETERIORATION
* Refer to 323 Workshop Manual f1203-1 O-89F (Europe) 12041U-89F (Australia)].
F2-38

F2 TROUBLESHOUTING GUIDE
I 22 KNOCKtNG [8P TURBO] I
IESCW-
l Abnormal combustron accompanied by audible “pinging” noise rim
TROUBLESHOOTING HtNTS]
3 incorrect ignition timing (Too advanced) @ Low octan fuel used
2
Knock control system malfunction @ Air/Fuel mixture lean
3 Carbon deposits in cylinder l Fuel injection amount not correct
3 Overheating l Fuel line pressure decreases while accelerating
TEP INSPECTION ACTlON
1
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’
ignition timing: BTDC 10 f lo
No Adjust
2 Check if “00” is displayed on Self-Diagnosis Yes Go to next step
Checker with igmtlon switch UN*
No Matf unction Code No. displayed
Check for cause (Refer to specified
check sequence) *
“88” flashes
Check ECU terminal 1 F voltage
Vottage: Approx. 12V
(Ignition switch ON) 0 page FZ-60
4 If OK, replace ECU
W: SELF TEST
4 If not OK, check wiring between
ECU and Self-Diagnosis Checker
3 Check for correct fuel line pressure at idle* Yes Check if fuel Iine pressure decreases
when accelerating quickly
Fuel line pressure:
265-314 kPa (2.7-3.2 kg/cm2, 38-46 psi)
(vacuum hose to pressure regulator dis-
connected) 4 If decreases, check for clogging
between fuel pump and pressure
regulator
e If no decrease, go to next step
No tow pressure Check
fuel line pressure while pinching
fuel return hose
3 If fuel line pressure quickly in-
creases, check pressure
regulator*
4 If fuel line pressure gradually in-
creases, check for clogging be-
tween fuel pump and
pressure
regutator
If not clogged, check fuel pump
maximum pressure*
- -
.-
Refer to 323 Workshop Manual [1203-IO-89f (Europe} or t204-IO-89f (Australia)]. F2-40

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.

FUEL SYSTEM F2
FUEL TANK
Removal I inspection / Instatlation
Warning
l Before performing the following operation, release the fue1 pressure from the fuet system to
reduce the possibitity of injury or fire. (Refer to page F2-50.)
l When removing the fuel tank, keep sparks, cigarettes, and open flames away from it.
l Before repairing the fuel tank, clean it throughly with steam to remove all explosive gas.
1. Remove in the order shown in the figure.
2. Inspect the fuel tank
components and repair or replace as necessary.
3. tnstall in the reverse order of removal, referring to Installation Note.
FUEL PUMP TRANSFER PUMP
0 SEAL RUBBER, REPLACE 7
A SSL
40-55 (4.1-56, 30-41)
N-m {m-kg, Mb)
93GOF2-771
F2-51