Grand Prix V6-191 3.1L (1989)
CHART C-2B
IDLE AIR CONTROL (IAC) CIRCUIT
2.8L (VIN W) & 3.1L (VIN T) "W" CARLINE (PORT)
Circuit Description:
Code 35 will set when the closed throttle engine speed is 300 rpm above or below the desired (commanded) idle speed for 50 seconds. Review the
general description of the IAC operation in Section "C2".
Test Description:
Numbers below refer to circled numbers on the diagnostic chart.
1.
Continue with test even if engine will not idle. If idle is too low, "Scan" will display 80 or more counts, or steps. If idle is high it will display "0"
counts. Occasionally an erratic or unstable idle may occur. Engine speed may vary 200 rpm or more up and down. Disconnect IAC. If the
