NEW SPARK PLUGS RELEASED (REDUCES BOOT STICKING)

Subject: NEW SPARK PLUGS

Models Affected:1992 BONNEVILLE, AND TRANS SPORT MODELS W/3800 TPI ENGINE; BONNEVILLE W/3800 SUPERCHARGED ENGINE; GRAND AM W/3300 MFI ENGINE

This bulletin is being revised to delete the Grand Prix models. This bulletin cancels and replaces bulletin 92-6-36 issued 4192. Please discard bulletin 92-6-36.

This bulletin is to inform technicians of a change in the spark plugs for vehicles with the 3300 MFI (Code N) engine, the 3800 TPI (Code L) engine, and the 3800 Supercharged (Code 1) engine.

In February of 1992, a new spark plug was released in production for the engines listed above to improve the spark plug to spark plug boot connection.

Exposure to underhood temperatures over periods of time has the tendency to increase the bond between the boot and the spark plug ceramic. In the past, different lubricants have been used in the spark plug boots with varying success. This new spark plug was released to reduce this bonding condition and to improve the dielectric strength between the plug and the boot.

This new spark plug can be visually identified by its smooth ceramic surface, the ridges have been removed (see figure 1). These new spark plugs have an anti-stick material coating baked onto the spark plug's outer ceramic surface. This coating is clear with a slightly waxy feel. To further help identify, the new spark plug, the type number has been changed to 41-600 from R45LTS6.

To maintain the reduced bonding characteristics, the Service Replacement Spark Plug 41-600 must be used, Service Package Number 5614253. The 41-600 Spark Plug is the recommended plug to use in all 1992 models listed above.

PARTS INFORMATION:

Parts are currently available from GMSPO.

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.