Pontiac Fiero 1988 Service Manual page 632

DRIVEABILITY AND EMISSIONS - FUEL INJECTION (PORT) 6E3-A-49
CODE 35
IDLE SPEED ERROR
2.8L "P" SERIES (PORT)
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9 ENGINE IDLING AT NORMAL
OPERATING TEMPERATURE.
• NOTE RPM IN PARK OR NEUTRAL.
• IGNITION " O F F " FOR 10 S E C
• START ENGINE AND IMMEDIATELY
NOTE RPM.
IDLE RPM, NO INCREASE
WILL NOT RETURN TO IDLE
RPM RECORDED ABOVE .
• IGNITION " O F F " .
• DISCONNECT IAC VALVE HARNESS.
• IGNITION " O N " , ENGINE STOPPED.
• GROUND DIAGNOSTIC TEST TERMINAL.
• CONNECT A TEST LIGHT BETWEEN EACH IAC
HARNESS CONNECTOR TERMINAL AND GROUND.
IDLE R P M , INCREASE
I
© IDLE ENGINE FOR 1 MINUTE
AND NOTE RPM.
RETURNS TO IDLE RPM RECORDED ABOVE .
IDLE AIR CONTROL CIRCUIT OK.
SEE FACING PAGE "DIAGNOSTIC AIDS"
NO LIGHTS, ONE OR
MORE CIRCUITS.
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CHECK FOR OPEN OR SHORT TO
GROUND IN CIRCUIT WITH NO LIGHT.
I
ARE ALL CIRCUITS O K '
3
YES
I
CHECK RESISTANCE ACROSS IAC COILS. SHOULD BE
MORE THAN 20 OHMS BETWEEN IAC TERMINALS
OPPOSITE HARNESS CONNECTOR TERMS. " A " TO " B "
AND " C " T O " D "
LIGHT STEADY OR
FLASHING ALL CIRCUITS.
FAULTY IAC CONNECTION
OR IAC V A L V E .
NO
REPAIR WIRING AND
RECHECK.
OK
FAULTY ECM CONN.
OR ECM.
NOT OK
REPLACE IAC VALVE
AND RETEST.
CLEAR CODES AND CONFIRM " C L O S E D L O O P " OPERATION AND NO "SERVICE ENGINE S O O N " LIGHT.
3-31-87
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