Mazda MX-6 1998, Руководство по ремонту

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TROUBLESHOOTING [ENGINE CONTROL FS]
STEP INSPECTION ACTION
3 CHECK EVAP SYSTEM FOR STUCK OPEN
VALVE
• Key off.
• Disconnect hoses at purge solenoid valve.
• Connect vacuum pump to charcoal canister
at purge solenoid valve.
• Apply -5 .3 kPa {-406 mmHg, -1 6 InHg} of
vacuum to purge solenoid valve.
• Does the purge solenoid valve hold
vacuum for 20 seconds?
Yes Go to next step.
No REPLACE purge solenoid valve.
RECONNECT all components.
RESET PCM to completely clear DTCs.
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After Repair Procedure
COMPLETE OBD II Drive Mode.
RERUN OBD Test.
4 CHECK IAC VALVE ASSEMBLY FOR
PROPER FUNCTION
• Key on, engine running.
• Bring engine to normal operating
temperature.
• Transaxle in Park or Neutral.
• Disconnect IAC valve assembly connector.
•
Does RPM drop or engine stall?
Yes Go to next step.
No INSPECT throttle body for damage or defect.
SERVICE as necessary.
If okay, REPLACE IAC valve assembly.
RESET PCM to completely clear DTCs.
ty After Repair Procedure
COMPLETE OBD II Drive Mode.
RERUN OBD Test.
5 CHECK IAC CIRCUIT FOR SHORT TO GND
• Key off.
• Disconnect NGS tester from DLC.
• IAC valve disconnected.
• Disconnect PCM. Inspect for damaged or
pushed out pins, corrosion, loose wires,
etc. Service as necessary.
• Measure resistance between Test Pin 83
and Test Pins 51 and 103 at breakout box.
• Is each resistance greater than 10,000
ohms?
Yes For Fast Idle Symptom currently present:
REPLACE PCM.
REMOVE breakout box.
RECONNECT all components.
RERUN OBD Test.
All others:
RECONNECT all components.
Go to next step.
No SERVICE short circuit.
RECONNECT all components.
RERUN OBD Test.
6
CHECK IAC SYSTEM FOR INTERMITTENT
OPEN OR SHORT
• NGS tester connected.
• Key on, engine running.
• Access IAC and RPM PIDs.
• With engine at normal operating
temperature and all accessories off, IAC
duty cycle should between 20% and 40%.
• Observe IAC and RPM PIDs for indication
of fault while performing following at idle:
• Lightly tap on IAC valve assembly and
wiggle harness connector to simulate
road shock
• Grasp vehicle harness closest to IAC
valve assembly. Shake and bend small
section of harness from IAC valve to
dash panel and from dash panel to PCM
• Do IAC or RPM PIDs suddenly change
indicating a fault?
Yes ISOLATE fault and SERVICE as necessary.
RECONNECT all components.
RESET PCM to completely clear DTCs.
c r After Repair Procedure
COMPLETE OBD II Drive Mode.
No For Idle quality, starting, or stalling symptoms
currently present:
REPLACE IAC valve assembly.
RECONNECT all components.
RESET PCM to completely clear DTCs.
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t
After Repair Procedure
COMPLETE OBD II Drive Mode.
Othres:
Unable to duplicate and/or identify fault at this time.
Intermittent poor connection or component malfunction
(REPAIR or REPLACE as necessary).
Go to SYMPTOM TROUBLESHOOTING No.27.
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