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4
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HARD TO START/LONG CRANK/ERRATIC START/ERRATIC CRANK
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|---|---|
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DESCRIPTION |
• Starter cranks engine at normal speed but engine requires excessive cranking time before starting.
• Battery is in normal condition.
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POSSIBLE CAUSE |
• Spark leakage from high-tension leads
• Vacuum leakage
• Poor fuel quality
• Starting system malfunction
• Spark plug malfunction
• Air leakage from intake-air system
• Erratic signal from CKP sensor
• Erratic signal from CMP sensor
• Improper air/fuel mixture ratio control
• Air cleaner restriction
• IAC valve malfunction
• PCV valve malfunction
• Inadequate fuel pressure
• Purge solenoid valve malfunction
• MAF sensor contamination
• Restriction in exhaust system
• EGR valve malfunction
• Pressure regulator malfunction
The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before performing the fuel system services:
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Diagnostic procedure
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STEP
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INSPECTION
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RESULTS
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ACTION
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|---|---|---|---|
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1
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Inspect for following:
• Vacuum leakage
• Proper fuel quality (e.g. proper octane, contamination, winter/summer blend)
• Loose bands on intake-air system
• Cracks on intake-air system parts
• Air cleaner restriction
Are all items okay?
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Yes
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Go to next step.
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No
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Service as necessary.
Repeat Step 1.
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2
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Connect WDS or equivalent to DLC-2.
Retrieve any KOEO and KOER DTC.
Is any KOEO or KOER DTC displayed?
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Yes
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DTC is displayed:
Go to appropriate DTC test.
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No
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No DTC is displayed:
Go to next step.
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3
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Is engine overheating?
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Yes
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Go to symptom troubleshooting "No.17 Cooling system concerns - Overheating".
|
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No
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Go to next step.
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4
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Inspect for cracks on high-tension leads.
Are there any cracks on high-tension leads?
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Yes
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Repair suspected high-tension leads.
|
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No
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Go to next step.
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5
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Inspect spark plug conditions.
Is spark plug wet, covered with carbon or grayish white?
|
Yes
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Spark plug is wet or covered with carbon:
Inspect for fuel leakage from fuel injector.
Spark plug is grayish white:
Inspect for clogged fuel injector.
|
|
No
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Install spark plugs on original cylinders.
Go to next step.
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6
|
Visually inspect CKP sensor and teeth of crankshaft pulley.
Are CKP sensor and teeth of crankshaft pulley okay?
|
Yes
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Go to next step.
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No
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Replace malfunctioning parts.
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7
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Measure gap between CKP sensor and teeth of crankshaft pulley.
Specification 0.5-1.9 mm {0.020-0.75 in}
Is gap within specification?
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Yes
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Go to next step.
|
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No
|
Adjust CKP sensor.
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8
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Remove and shake PCV valve.
Does PCV valve rattle?
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Yes
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Go to next step.
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No
|
Replace PCV valve.
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9
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Install fuel pressure gauge between fuel pipe and fuel distributor.
Connect a jumper wire between F/P terminal at DLC-2 in engine compartment and GND.
Turn ignition switch to ON position.
Is fuel line pressure correct with ignition switch ON?
|
Yes
|
Go to next step.
|
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No
|
Zero or low:
Inspect for clogged fuel line.
If okay, replace fuel pump unit.
High:
Replace fuel pump unit.
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10
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Is fuel line pressure held after ignition switch is turned off?
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Yes
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Go to next step.
|
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No
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Inspect fuel injector.
If fuel injector is okay, replace fuel pump unit.
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11
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Disconnect a vacuum hose from purge solenoid valve and plug opening end of vacuum hose. Attempt to start engine.
Is starting condition improved?
|
Yes
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Inspect if purge solenoid valve sticks open.
|
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No
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Go to next step.
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12
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Inspect MAF sensor for contamination.
Is there any contamination?
|
Yes
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Replace MAF sensor.
|
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No
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Go to next step.
|
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13
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Is there restriction in exhaust system?
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Yes
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Inspect exhaust system.
|
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No
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Go to next step.
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14
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Inspect engine condition while tapping EGR valve housing. Does engine condition improve?
|
Yes
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Replace EGR valve.
|
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No
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Go to next step.
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15
|
Inspect starting system.
(See STARTER INSPECTION [L3].)
Is starting system normal?
|
Yes
|
Inspect for loose connectors or poor terminal contact. If okay, remove EGR valve and visually inspect for mechanically stuck EGR valve.
|
|
No
|
Repair or replace components as required.
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16
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Verify test results.
• If okay, return to diagnostic index to service any additional symptoms.
• If malfunction remains, replace PCM.
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