90CS Quattro V6-2.8L (AAH) (1994)
Idle Air Control Valve: Testing and Inspection
Idle Air Control (IAC) valve.
NOTE:
For function testing of the idle air control valve, also see, On Board Diagnostic (OBD) "Read Measuring Value Block" function 08, display
groups 004 and/or 018. See: Computers and Control Systems/Testing and Inspection
Electrical check
Idle Air Control Valve Connection
-
Disconnect harness connector from IAC valve.
Idle Air Control Valve Testing
-
Measure resistance on IAC valve.
^
Specified value: 7-11 (ohms)
If specified values are not obtained:
-
Replace IAC valve.
NOTE:
At room temperature, the resistance lies lower in the tolerance range; with the engine warmed to operating temperature, it is higher in the
tolerance range.
Mechanical check
-
Remove idle air control valve.
Idle Air Control Valve
-
Check rotary slide valve (arrow) for signs of scoring (by visual inspection).
CAUTION!