Cutlass Supreme FWD V6-189 3.1L (1989)
Oxygen Sensor: Technical Service Bulletins
Engine Controls - New Chart C-2B (IAC) & Code 44 (O2)
SUBJECT:
SERVICE MANUAL UPDATE - SECTION 6E -
DRIVEABILITY AND EMISSIONS - CHART C-2B/CODE 44
MODELS/YEARS:
1989 CUTLASS CIERA, CUTLASS CRUISER AND
CUTLASS SUPREME MODELS EQUIPPED WITH 2.8L/3.1L (VIN T, W)
NUMBER:
89-T-42
CORP. REF. NO: 916504
DATE:
February 1989
SECTION:
6E
This bulletin adds CHART C-2B (Idle Air Control Circuit) to Section 6E "Driveability And Emissions" of the Service Manual for the 1989 Cutlass Ciera
and Cutlass Supreme carlines with 2.8L LB6 (VIN W) and 3.1L LH0 (VIN T) engines.
This bulletin also revises Code 44 - Oxygen Sensor Circuit (Lean Exhaust Indicated) facing page "Diagnostic Aids" in Section 6E in the above
mentioned service manuals. Code 44 may set as a result of a faulty in the Idle Air Control (IAC) Circuit.
CHART C-2B
IDLE AIR CONTROL (IAC) CIRCUIT
Circuit Description:
2.8L (VIN W) "A" CARLINE (PORT)
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".
