Mazda 626 Station Wagon, Руководство по ремонту

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TROUBLESHOOTING
Diagnostic Procedure
STEP INSPECTION RESULTS
ACTION
1 Verify following:
• External fuel shut off or accessory
• Fuel quality (e.g. proper octane,
contamination, winter/summer blend)
• No air leakage from intake-air system
• Proper sealing of intake manifold and
components attached to intake manifold;
such as EGR valve, I AC valve
• Ignition wiring
• Electrical connections
• Fuses
• Smooth operation of throttle valve
Are all items okay?
Yes Go to next step.
No
Service as necessary.
Repeat Step 1.
2
Connect NGS tester to DLC.
Turn ignition switch on.
Retrieve any DTC.
Is any DTC displayed?
Yes
DTC is displayed:
Go to appropriate DTC test.
No No DTC is displayed:
Go to next step.
3 Is engine overheating? Yes Go to symptom troubleshooting No. 16 “Cooling
system concerns - Overheating”.
No Go to next step.
4 Note
• Following test is for engine running rough idle
with A/C on concerns. If other symptoms
exist, go to next step.
Connect pressure gauge to A/C low and high
pressure side lines.
Start engine and run it at idle.
Turn A/C switch on.
Measure low side and high side pressures.
(See Section U)
Are reading pressures within specifications?
Yes Go to next step.
No If A/C is always on, go to symptom
troubleshooting No.23 “A/C is always ON or A/C
compressor runs continuously”.
For other symptoms, inspect following:
• Refrigerant charging amount
• Condenser fan operation
5 Note
• Following test is for engine running rough
with P/S on. If other symptoms exist, go to
next step.
Start engine and run it at idle.
Access PSP SW PID.
Inspect if PSP SW PID is on while turning
steering wheel right to left.
Is PSP SW PID okay?
Yes Go to next step.
No
Inspect power steering pressure switch
operation and wiring harness between power
steering pressure switch connector and PCM
connector terminal 31.
6 Visually inspect CKP sensor and teeth of
crankshaft pulley.
Are CKP sensor and teeth of crankshaft pulley
okay? Yes Go to next step.
No
Replace malfunctioning parts.
7 Measure gap between CKP sensor and teeth of
crankshaft pulley.
Specification
0.5— 1.5 mm {0.020—0.059 in}
Is gap within specification?
Yes Go to next step.
No Adjust CKP sensor.
8 Inspect for cracks on high-tension leads.
Is there any crack on high-tension leads? Yes Repair suspected high-tension leads.
No Go to next step.
9
Inspect spark plug conditions.
Is spark plug wet, covered with carbon or
grayish white?
Yes Spark plug is wet or covered with carbon:
Inspect for fuel leakage from injector.
Spark plug is grayish white:
Inspect for clogged fuel injector.
No Install spark plugs on original cylinders.
Go to next step.
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