When installing spark plugs in the 3.1 L engine, use the following revised specification.
Cast Iron or Aluminum Heads, 15 N.m (1 1 Lb. Ft.)
Mark a reference to this bulletin in your copy of the following service manuals:
1991 Cutlass Supreme Pages 6D4 - 4, 5, 7
Silhouette Pages 6A4 - 20, 46 and 6D4 - 6
1990 Cutlass Supreme Pages 6D4 - 3, 4, 5
Silhouette Pages 6A4 - 17, 41 and 6D4 - 6
1989 Cutlass Supreme Pages 6A5-16 & 26 and 6D4-4
Cutlass Ciera/Cutlass Cruiser Pages 6A4-14 & 23
1988 Cutlass Supreme Pages 6A3-16 & 26 and 6D4-3
Cutlass Ciera/Cutlass Cruiser Pages 6A4-16 & 12
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.