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For 1990-2009 cars only

TRANSAXLE BUMPS AND/OR MAKES A RATCHETING SOUND

SUBJECT: Transaxle Bumps and/or Makes a Ratcheting Sound in 1st Gear Under Very Light Throttle (Install New PCM Calibration)

MODELS AFFECTED: 1996 Saturns equipped with PCM powertrain control module, part number (hardware I.D.) of 21023708-MP6 or 21023051-MP7 and 1997 Saturns equipped with MP6/MP7 automatic transaxles built up to and including VIN VZ251121.

CONDITION: The transaxle may bump and/or make a ratcheting sound in 1st gear when driving under a very light throttle condition, with engine at normal operating temperature. These conditions may be intermittent and may occur up to and including six percent throttle. These conditions will not exist when vehicle is launched under heavier throttle positions above six percent.

CORRECTION: If the vehicle is a 1997 model built before and including VIN VZ251121, or if the vehicle is a 1996 model with PCM powertrain control module, part number (hardware I.D.) of 21023708 - MP6 or 21023051 - MP7, refer to procedures in this bulletin to verify and repair conditions mentioned above.

IMPORTANT: To check powertrain control module (PCM) part number (hardware I.D.), connect Scan tool to data link connector (DLC) and scroll to PCM PART # in the VEHICLE I.D. table.

PROCEDURE

1. Install new PCM/TC calibration according to the calibration chart below. (Refer to "Reprogramming EEPROM" in the "Service Stall System User Guide.")

IMPORTANT: Version 38.5 or greater service stall system (SSS) software is required for this flash process. Verify the SSS is version 38.5 or greater.

If SSS version 38.5 or greater is not available, call Saturn Customer Support Center at 1 (800) 7SATURN (1 (800) 772-8876), prompt 3. In Canada, call 1 (800) 828-6860 for English, or 1 (800) 503 - 3222 for French.

END SERVICE MODEL Type DESCRIPTION PCM PART# -------- ------ --------------------------------------------- --------- 1996 SOHC (L24)/AUTOMATIC TRANSAXLE MP6 21008695 Flash B/A California First Gear Bump Calibration 21023775 21008694 Flash B/A Federal First Gear Bump Calibration 21023775 21008699 Flash B/A Canada/Taiwan First Gear Bump Calibration 21023775

1996 DOHC (LL0)/AUTOMATIC TRANSAXLE MP6 21008692 Flash P/A Federal and California First Gear Bump 21023776 Calibration 21008698 Flash P/A Canada/Taiwan First Gear Bump Calibration 21023776

1996 SOHC (L24)/AUTOMATIC TRANSAXLE MP6 21008695 Flash B/A California First Gear Bump Calibration 21023775 21008694 Flash B/A Federal First Gear Bump Calibration 21023775 21008699 Flash B/A Canada/Taiwan First Gear Bump Calibration 21023775

1997 DOHC (LL0)/AUTOMATIC TRANSAXLE MP7 21008693 Flash P/A California First Gear Bump Calibration 21023776 21008692 Flash P/A Federal First Gear Bump Calibration 21023776 21008698 Flash P/A Canada/Taiwan First Gear Bump Calibration 21023776 21008700 Flash P/A Japan First-Gear Bump Calibration 21023807

2. To verify repair, perform the following test:

a. Operate vehicle until transaxle temperature reaches 70*C (158*F).

b. Place vehicle in Park.

c. Apply parking brake.

d. Connect Scan tool and scroll to monitor transaxle oil pressure.

e. Place foot firmly on brake.

CAUTION:

TO PREVENT POSSIBLE PERSONAL INJURY, MAKE SURE WHEN PERFORMING THE NEXT STEPS THAT THERE ARE NO PERSONS OR OBJECTS IN FRONT OF THE VEHICLE.

f. Place vehicle in Drive.

g. Lightly engage throttle (less than two percent as monitored on the Scan tool), while monitoring transaxle oil pressure, slowly increase throttle until transaxle oil pressure increases to above 800 kPa (87 psi), or until a bump and/or racheting sound is heard, and release the throttle.

- If a bump and/or ratcheting sound is not heard when transaxle oil pressure has increased to above 800 kPa (87 psi) the vehicle has been repaired.

- If a bump and/or ratcheting sound is heard before transaxle oil pressure has reached 800 kPa (87 psi), refer to the appropriate year automatic transaxle service manual for DTC P0731, "Transaxle 1st Gear - No 1st Gear" and follow the diagnostic trouble tree.

CLAIM INFORMATION: To receive credit for this repair during the warranty coverage period, submit a claim through the Saturn Dealer System as follows:

Labor Case Operation Type Description Code Time ---- --------------------------- ----- ---------- VW Install New PCM Calibration T9738 0.3 hrs

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.