POOR ENGINE PERFORMANCE ON THE 5.0L 307 V-8 ENGINE EQUIPPED WITH A 200-4R TRANSMISSION AND 4BBL CARBURETOR CAN OCCUR ON DECELERATION, DUE TO BUILD UP OF HIGH MANIFOLD VACUUM. THE HIGH VACUUM SEATS THE IDLE LOAD COMPENSATOR PLUNGER WHICH ALLOWS THE THROTTLE LINKAGE TO REST ON THE IDLE STOP SCREW LOCATED ON THE THROTTLE BODY. IF THE IDLE STOP SCREW IS NOT ADJUSTED AS DESCRIBED IN SECTION 6C OF THE 1981 SERVICE MANUAL THE IDLE CAN DROP BELOW THE SPECIFIED RPM CAUSING POOR ENGINE PERFORMANCE.
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.