INTRO. OF GEN II SPECIAL (NEWLY DESIGNED PCM)

SUBJECT: INTRODUCTION OF THE GEN (GENERATION) II SPECIAL

MODELS AFFECTED: 1993 GRAND PRIX MODELS WITH 3.1 ENGINE (RPO LH0)

A newly designed Powertrain Control System will be incorporated on the 1993 Grand Prix when equipped with all three of the following Regular Production options (RPO's):

- M13 - 4T60E 4 Speed Automatic Transmission - LH0 - 3.1L V-6 Engine - NB2 - California Emissions

This system will be collectively referred to as Gen (Generation) II Special.

The 1993 GEN II Special 3.1L system includes:

- Sequential Fuel Injection - Includes use of a camshaft sensor, 2 crank sensors and all new Powertrain Control Module (PCM).

- Heated Oxygen Sensor.

- Air Injection Reaction (AIR) system - Belt driven off engine.

- Improved, Forward Mounted Catalytic Converter.

- Unique CAMS/TECH 1 data stream communication.

A carryover powertrain control system will be utilized on all 3.1L Federal Emission as well as all 3.1L 3-speed Automatic Transmission vehicles.

PROCEDURE:

---------- To gain early field information and assist dealers in giving expedient service to customers, vehicles equipped with GEN II Special will be supported by a specially dedicated team of field engineers. If a GEN II Special vehicle exhibiting an engine driveability or PCM problem comes to your dealership for service, please instruct your service personnel to contact the GEN II Special "HOTLINE" at:

1-800-257-7519

The hotline operator will perform a brief interview to collect pertinent information about the vehicle and the apparent problem. If the problem is not related to driveability or engine performance, normal diagnostics and repair procedures should be utilized. Based on the nature and type of problem determined, your service manager will be contacted by a specially assigned field engineer to determine the best and most expedient fix for the problem.

As a reminder, the CAMS and TECH 1 diagnostic equipment will be programmed to flag vehicles equipped with this system and remind the service technician that the "800" number must be contacted prior to performing any driveability/performance diagnosis or repairs. This "800" number and dated reminder also will be printed on the PCM.

It is anticipated that this early exposure program will help identify and correct any problems that might arise with this new system. Feedback from all dealers involved is critical.

This program will be in effect from the start of the 1993 model year until December 23, 1992.

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.