For 1990-2009 cars

# TIMING ADJ. PROCEDURE BASE ENGINE TIMING

INCLUDED IN THIS BULLETIN IS A CHART DESCRIBING PROCEDURES REQUIRED TO SET BASE ENGINE TIMING ON ALL 1981 AND 1982 GENERAL MOTORS ENGINES. THE INFORMATION PROVIDED IS BASIC, AND THE VEHICLE TUNE-UP LABEL, LOCATED IN THE ENGINE COMPARTMENT, SHOULD BE REFERRED TO WHENEVER MAKING ENGINE ADJUSTMENTS. * SEE BULLETIN FOR ADDITIONAL INFORMATION *

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.