Mazda 626 Station Wagon, Workshop Manual

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ON-BOARD DIAGNOSTIC
STEP INSPECTION ACTION
6 INSPECT INTAKE AIR SYSTEM
• Inspect air cleaner element clogs.
• Is air cleaner element clogs?
Yes Replace air cleaner element, then go to Step 13.
No Go to next step.
7
INSPECT PURGE CONTROL SYSTEM
• Inspect purge control system.
(See F-153 Purge Control Inspection)
• Is purge control system okay?
Yes Go to next step.
No Repair or replace malfunctioning part as Purge
Control Inspection, then go to Step 13.
8 INSPECT EGR CONTROL SYSTEM
• Inspect EGR control system.
(See F1-152 EGR Control Inspection)
• Is EGR control system okay?
Yes Go to next step.
No Repair or replace malfunctioning part as EGR Control
Inspection, then go to Step 13.
9 INSPECT FUEL LINE PRESSURE
• Inspect fuel line pressure.
(See Section F)
• Is fuel line pressure okay?
Yes Go to next step.
No Repair or replace malfunctioning part as FUEL LINE
PRESSURE INSPECTION, then go to Step 13.
10 INSPECT FUEL INJECTOR OPERATION
• Inspect fuel injector inspection.
(See Section F)
• Is fuel injector operation okay?
Yes Go to next step.
No Repair or replace malfunctioning part as Fuel Injector
Operation Inspection, then go to Step 13.
11
INSPECT SEALING OF ENGINE COOLANT
PASSAGE
Warning
• Removing radiator cap when radiator is
hot is dangerous. Scalding coolant and
steam may shoot out and cause
serious injury.
• When removing radiator cap, wrap a
thick cloth around and turn It slowly.
• Remove radiator cap.
• Implement procedure to bleed air from engine
coolant, then run engine at idle.
• Is there any small bubble, which makes
engine coolant white at filling opening.
Note
• Large bubble are normal since they are
remaining air coming out from engine
coolant passage.
Yes Air gets in from poor sealing to head gasket or other
areas between combustion chamber and engine
coolant passage. Repair or replace faulty parts, then
goto Step 13.
No Go to next step.
12 INSPECT ENGINE COMPRESSION
• Inspect engine compression.
(See Section B)
• Is engine compression okay?
Yes Go to next step.
No Repair or replace malfunctioning part as
COMPRESSION INSPECTION, then go to next step.
13 VERIFY TROUBLESHOOTING OF DTC P1170
COMPLETED
• Turn ignition key to ON. (Engine OFF).
• Clear DTC from memory using NGS tester.
• Preform following procedure twice.
— Start engine.
— Access ECT and RPM PIDs using NGS
tester.
— Make sure that ECT PID is above 80 °C
{176 °F}
— Increase and keep speed above 1,500
rpm for at least 20.4 seconds.
• Is same DTC present?
Yes Replace PCM, then go to next step.
No Go to next step.
14
VERIFY AFTER REPAIR PROCEDURE
• Perform “After Repair Procedure".
(See F1 36 AFTER REPAIR PROCEDURE)
• Are any DTC present?
Yes Go to applicable DTC inspection.
(See F1-37 DTC TABLE)
No Troubleshooting completed.
F1-67