1990 MAZDA 232 overheating

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*
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Refer to 323 Workshop Manual [1203-IO-89f (Europe} or t204-IO-89f (Australia)]. F2-40