Cobalt L4-2.0L SC VIN P (2005)
Idle Speed: By Symptom
Technical Service Bulletin # 06-06-04-039
Date: 060810
Engine Controls - Fluctuating/Unstable Idle Speed
Bulletin No.: 06-06-04-039
Date: August 10, 2006
TECHNICAL
Subject:
Fluctuating, Unstable or Incorrect Engine Idle - LSJ (Reprogram ECM)
Models:
2005-2006 Chevrolet Cobalt SS Supercharged
2004-2006 Saturn ION Redline
with Ecotec(TM) 2.0L I-4 Engine (VIN P - RPO LSJ)
Condition
Some customers may comment that the engine idle may fluctuate (idle roll) a hundred rpm for several seconds when the engine is started hot or cold.
Further diagnostic investigation with a scan tool may not reveal the cause. No other driveability or performance concerns may be reported.
Cause
The most likely cause of this issue may be that the engine calibrations need to be updated to correct the fluctuating engine idle
Correction
DO NOT replace the throttle body, the ECM or any other parts.
Important:
^
Chevrolet Dealers: The ECM calibration is available to dealerships as part of TIS2000 incremental satellite update version 6.5, which was
broadcast to dealers on June 12, 2006 or later. For the dealerships that use CDs, they were mailed out June, 2006 or later.
^
Saturn Retailers: Before installing the new ECM calibration, make sure the Saturn Service Stall (SSS) version is TIS 6.5 2006 or later.
^
While the ignition is OFF, apply the parking brake to disable the daytime running lights (DRLs) prior to starting reprogramming procedures
^
The technician must select the "Reprogram" option in order to reprogram the ECM.
^
Reprogram the ECM with the latest calibration. This calibration, or any that follow, is designed to address this fluctuating engine idle concern.
Refer to Service Programming System (SPS) in SI for reprogramming procedures. As always, make sure your Tech 2(R) is updated with the
latest software version.
Warranty Information
For vehicles repaired under warranty, use the table.
