The attached handy Pocket Guide(s) are being sent to GM dealerships to assist them with quick diagnostics and repair of passenger car driveability conditions.
This was deemed desirable due to the volume of service bulletins and information published on driveability and due to the changes in engine design and diagnostics over the past few years. The Pocket Guide(s) attached to this bulletin should be provided to
the driveability technicians at your dealership. They summarize all information into a "condition, cause, and correction" format specific to resolution and the "do's and don'ts" for each model year engine.
All Service Bulletin numbers are current and correct as of April 20, 1990, but are subject to change. This Pocket Guide may not be updated to include future bulletins.
For further information regarding the pocket guide, contact your local zone or branch office.
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.