Mazda 626 Station Wagon, Руководство по ремонту

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TROUBLESHOOTING
Diagnostic Procedure
STEP INSPECTION RESULTS
ACTION
1 What color is smoke coming from exhaust
system? Blue Burning oil is indicated. Go to next step.
White
Water in combustion is indicated. Go to Step 3.
Black Rich fuel mixture is indicated. Go to Step 4.
2 Remove and shake PCV valve.
Does PCV valve rattle? Yes
Inspect for following:
• Damaged valve guide, stems or valve seals
• Blocked oil drain passage in cylinder head
• Piston rings is not seated, seized or worn
• Damaged cylinder bore
If other drivability symptoms are present, return
to diagnostic index to service any additional
symptoms.
No
Replace PCV valve.
3 Does cooling system hold pressure? Yes Inspect for following:
• Cylinder head gasket leakage
• Intake manifold gasket leakage
• Cracked or porous engine block
If other drivability symptoms are present, return
to diagnostic index to service any additional
symptoms.
No Inspect for cause.
4 Inspect for following:
• Air cleaner restriction
• Collapsed or restricted intake-air system
• Restricted fuel return line
Are all items okay?
Yes Go to next step.
No Service as necessary.
Repeat Step 4.
5 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.
6 Install fuel pressure gauge between fuel main pipe
and fuel distributor.
Start engine and run it at idle.
Measure fuel line pressure at idle.
Is fuel line pressure correct at idle?
Fuel line pressure
210—260 kPa {2.1—2.6 kgf/cm2, 30—36 psi}
Yes Go to next step.
No Zero or low:
• Inspect fuel pump unit circuit.
• Inspect for open fuel pump body relief valve.
• Inspect for fuel leakage inside pressure
regulator.
• Inspect for clogged main fuel line.
High:
• Inspect pressure regulator for high pressure
cause.
• Inspect for clogged fuel return line.
7 Does fuel line pressure remain within specification
for 60 seconds when ignition switch is turned on?
Fuel line pressure
210—260 kPa {2.1—2.6 kgf/cm2, 30—36 psi}
Yes
Go to next step.
No Inspect pressure regulator for high pressure
cause.
8 Is strong blue spark visible at each disconnected
high-tension lead while cranking engine? Yes
Inspect spark plugs and CMP sensor.
No Inspect following:
• High-tension leads
• Ignition coil and connector
9 Verify test results. If okay, return to diagnostic index to service any additional symptoms.
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