ENGINE STALLS AFTER INITIAL START/HESITATE OR SURGE. Saturn Saturn 1992

For 1990-2009 cars

# ENGINE STALLS AFTER INITIAL START/HESITATE OR SURGE

#### SUBJECT: Engine Stalls After Initial Start, or Hesitates During Launch, or Surges During Light Accelerations, DOHC (LLO) Engines (Install New PCM Calibration)

#### MODELS AFFECTED: All 1992 Saturns with DOHC (LLO) engines

#### CONDITION:

Some customers of 1992 Saturns, equipped with DOHC (LLO) engines may comment that the engine stalls after the vehicle is initially started, or hesitates on launch. Customers may also comment on a surge during light accelerations.

#### CAUSE:

Due to engine sensitivity to variations in cool ambient temperatures along with the new 1992 Federal regulations that address Spring and Summer fuel grade volatility, initial start - up and warm - up driveability has been impacted, especially on new engines.

CORRECTIVE ACTION: Verify that the start/stall condition occurs during initial start or vehicle hesitates during a launch or surges during light accelerations, then proceed with the Steps listed under "Procedure," on the next page.

#### PROCEDURE:

1. Using the Scan tool, check for PCM EC/TC codes and flags. If codes or flags are present, refer to the applicable diagnostic charts in the "Electronic Engine Controls Service Manual" and repair the condition. After verifying that condition has been repaired, download the new calibration according to Step 3.

2. If no codes or flags are present, monitor Scan tool data and verify all parameters are within specification. Refer to "Electronic Engine Controls Service Manual." If parameters are not within specification, repair the condition. After verifying that condition has been repaired, download the new calibration according to Step 3.

3. If no codes or flags are present and Scan tool data is within specification, download new calibration using the Saturn Service Stall System or refer to the "Electronic Engine Controls Service Manual."

IMPORTANT- Before installing a new calibration, make a note of the transaxle calibration installed, and download the same transaxle calibration with the correct engine calibration.

#### 1992 New Calibration - DOHC (LLO) Engines

TCM ECM

2548 3185 Automatic Transaxles before VIN NZ205625, excluding NZ200001 through NZ200100

8520 3185 All Other Automatic Transaxles 3183 Manual Transaxles

#### IMPORTANT: After the new calibration has been installed, vehicle must be driven until operating temperature is reached. This allows the PCM to relearn variations in the fuel system electronic controls that improve driveability and engine idle.

#### IMPORTANT: Verify that customer complaint has been repaired. If problem still exists, refer to diagnostic procedures in the "Fuel/Air Intake/Exhaust Service Manual," and "Electronic Engine Controls Service Manual."

CLAIM INFORMATION: To receive credit for this repair, submit a claim through the Saturn Dealer System as follows: Labor Case Operation Type Description Code Time ---- ----------- --------- ---- VW PCM EC/TC Calibration T9622 0.3 hrs (Includes PDT Parameter and Code/Flag Checks)

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.