Mazda MX-6 1998, Руководство по ремонту

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TROUBLESHOOTING [ENGINE CONTROL KL]
7 ENGINE RUNS ROUGH/ROLLING IDLE
DESCRIPTION
• Engine speed fluctuates between specified idle speed and lower speed and excessive engine shake
• Idle speed too slow and excessive engine shake
POSSIBLE
CAUSE
• Air leak from intake air system parts
• Spark leak from high-tension leads
• Improper operation of IAC valve
• Erratic or no signal from camshaft position (CMP) sensor
• Erratic signal from crankshaft position (CKP) sensor
• PCV valve malfunction
• Restriction in exhaust system
• Inadequate fuel pressure
• Fuel leak from fuel injector
• Engine overheating
• A/C system improperly operation
• Purge solenoid valve malfunction
• EGR valve malfunction
• Low engine compression
• Poor fuel quality
• Air cleaner restriction
• Electrical connector disconnection
• Fuel pump mechanical malfunction
• Fuel injector clogged
• Vacuum leak
Warning
Following troubleshooting flow chart contains fuel system diagnosis and repair procedures. Read
following warnings before performing fuel system service:
• Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep
sparks and flames away from fuel.
• Fuel line spills and leaks are dangerous. Fuel can ignite and cause serious injuries or death
and damage. Fuel can also irritate skin and eyes. To prevent this, always complete “ BEFORE
REPAIR PROCEDURE” and “AFTER REPAIR PROCEDURE” described in this manual.
cr 0 1 -1 4 BEFORE REPAIR PROCEDURE
er 0 1 -1 4 AFTER REPAIR PROCEDURE
STEP INSPECTION
ACTION
1 Verify following:
• External fuel shut off or accessory (ignition
switch, alarm etc).
• Fuel quality; such as proper octane,
contamination, winter/summer blend.
• No air leaks from intake air system.
• Proper sealing of intake manifold and
components attached to intake manifold;
such as EGR valve, IAC solenoid.
• Ignition wiring.
• Electrical connections.
• Fuses.
Are all items okay?
Yes Go to next step.
No Service as necessary and repeat step 1.
2 Retrieve and record any continuous memory,
KOEO and KOER DTCs.
Are there any DTC displayed?
Yes Go to appropriate DTC test.
No No DTCs displayed.
Go to next step.
3
Is engine overheating? Yes Go to flowchart 17 for "COOLING SYSTEM CONCERNS
OVERHEATING”.
No Go to next step.
0 1 -0 1 B -1 44