PleasureCraft Engine Group 5.0L, Руководство по диагностике

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7 - 4 Symptoms 5.0/5.7/6.0/8.1L
MEFI 4 - PCM
1. Check ECT sensor for being shifted in value.
2. With the engine completely cool, compare the ECT
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sensor temperature with an accurate reading of
ambient air temperature.
Are the temperatures within the specifi ed value of
each other? -12° C (10° F)
Go to Step 12 Go to Step 14
1. Using a scan tool, display ECT sensor temperature and
note value.
2. Check resistance of ECT sensor.
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3. Go to Engine Coolant Temperature Sensor Temperature
vs. Resistance value table on the facing page of DTC
14 in the
Diagnostics section.
Is resistance value of ECT sensor near the resistance of
the value noted? —
Go to Step 15 Go to Step 13
Locate and repair high resistance or poor connection in the
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ECT signal circuit or the ECT sensor ground.
Go to OBD
Is action complete? — System Check —
14
Replace the ECT sensor. Go to OBD
Is action complete? — System Check —
1. Check for intermittent opens or shorts to ground in the
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MAP sensor circuits.
2. If a problem is found, repair as necessary.
Go to OBD
Was a problem found? — System Check Go to Step 16
1. Check for proper operation of the TP sensor.
2. Check for throttle linkage sticking, binding or worn
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causing TP sensor voltage to be higher than normal.
3. If a problem is found, repair as necessary.
Go to OBD
Was a problem found? — System Check Go to Step 17
1. Check for proper operation of the IAC valve.
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•
Refer to Table A-8.
2. If a problem is found, repair as necessary.
Go to OBD
Was a problem found? — System Check Go to Step 18
1. Check for the following engine mechanical problems:
•
Low compression.
•
Leaking cylinder head gaskets.
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•
Worn or incorrect camshaft.
•
Proper valve timing/valve train problem.
•
Restricted exhaust system.
2. If a problem is found, repair as necessary.
Go to OBD
Was a problem found? — System Check Go to Step 19
Hard Start Symptom
Step Action Value Yes No