Mazda MX-6 1998, Workshop Manual

Page: 291 / 1282

TROUBLESHOOTING [ENGINE CONTROL KL]
STEP INSPECTION ACTION
10 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, accessories off and at idle,
IAC duty cycle should read between 20%
and 45%.
• Observe IAC and RPM PIDs for an
indication of fault while performing following
at idle:
• Lightly tap on IAC valve component and
wiggle harness connector to simulate
road shock
• Grasp vehicle harness closest to IAC
valve component. Shake and bend
small section of harness from IAC to
dash panel and from dash panel to PCM
• Do IAC or RPM PIDs suddenly change in
value indicating fault?
Yes
ISOLATE fault and SERVICE as necessary.
RECONNECT all components.
RESET PCM to completely clear DTCs.
tr
After Repair Procedure
COMPLETE OBD II Drive Mode.
RERUN OBD Test.
No For idle quality, starting, or stalling symptoms
currently present:
REPLACE IAC valve component.
RECONNECT all components.
RESET PCM to completely clear DTCs.
et
After Repair Procedure
COMPLETE OBD II Drive Mode.
All others:
Unable to duplicate and/or identify fault at this time.
Intermittent poor connection or component malfunction
(REPAIR or REPLACE as necessary).
Go to ENGINE SYMPTOM TROUBLESHOOTING No.27.
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