ION L4-2.2L VIN F (2004)
PROM - Programmable Read Only Memory: Customer Interest
Engine Controls - Erratic Engine Idle Speed/Stalling
Bulletin No.: 04-06-04-029A
Date: September 14, 2004
TECHNICAL
Subject:
Erratic Engine Speed Control at Closed Throttle - Elevated Engine RPM, Crank/No Start and/or Stall (Verify Engine Control Module [ECM]
Calibration, Reprogram ECM, if Necessary)
Models:
2003-2004 Saturn ION Vehicles with 2.2L Four-Cylinder Engine (VIN F - RPO L61)
Attention:
Fixed Operations Manager and Technician
Supercede:
This bulletin includes a revised service procedure with new calibrations. Please discard Corporate Bulletin Number 04-06-04-029 (Section 06 -
Engine/Propulsion System).
Condition
Some customers may comment on erratic engine performance at idle (closed throttle). One or more of the following conditions may be observed:
^
Engine stalls at idle or when coming to a stop (closed throttle).
^
Engine starts then stalls immediately.
^
Engine RPM flares without throttle input.
^
Idle Air Control (IAC) counts at idle (as viewed on the Tech 2 scan tool) are high or low (normal range is 25-85 counts).
Cause
Previous ECM software may not track IAC valve position accurately.
Correction
Verify current ECM calibration and reprogram ECM using Saturn Service Stall System version TIS 8.0 2004 or later data CD, if necessary. Refer to
service procedure.
Service Procedure
1.
With engine running at idle speed, monitor "IAC Position" using Tech 2 scan tool. Acceptable normal range at operating temperature with A/C
OFF is 25-85 counts.
2.
If IAC Position counts are out of the expected range and/or swing erratically, verify engine calibration and reprogram ECM if necessary. Refer to
"Verifying Calibration ID Number" and "Reprogramming ECM" procedures in this bulletin.
3.
If engine idle speed remains erratic after ECM reprogramming, refer to "Rough, Unstable, or Incorrect Idle and Stalling" diagnostic procedure in
the Engine section of the 2003 or 2004 Saturn ION Service Manual, Vol. 1 [for both 2003 and 2004 model year vehicles]).
Verifying Calibration ID Number
Important:
You must view calibration numbers using the Tech 2 Scan Tool and NOT the Saturn Service Stall System (SSS).
1.
Connect Scan Tool to the vehicle.
2.
Navigate to the 2.2L (VIN F) Powertrain Menu.
3.
Select ID INFORMATION.
