GM Service Manual Online
For 1990-2009 cars only

RADIO NOISE DUE TO IGNITION REPLACE BRUSH IN DIST.

SOME 1984 "B", "F", "G" AND Y" MODELS WITH (LG4) 5.0LAND (L83) 5.7L ENGINES MAY EXHIBIT A RADIO (AM AND/OR FM BAND) TICKING NOISE THE FREQUENCY OF THE TICKING INCREASES WITH INCREASED ENGINE R.P.M. THE CONDITION MAY BE DUE TO A NEW, LOWER RESISTANCE RESISTIVE BRUSH IN THE DISTRIBUTOR CAP AND IS FURTHER AGGRAVATED BY SILICONE GREASE ON THE CAP TERMINALS. REPAIRS CAN BE PERFORMED USING THE FOLLOWING PROCEDURE: 1. REPLACE THE EXISTING BRUSH (COMMONLY KNOWN AS THE CARBON BALL) AND SEAL WITH BALL 1989880 AND SEAL 1875962. (THE SEAL MUST BE REPLACED WHEN THE BALL IS REPLACED). 2. REMOVE ANY SILICONE GREASE FROM CAP TERMINALS AND REMOVE ANY CARBON DEPOSITS ON THE CONTACTS INSIDE THE DISTRIBUTOR CAP.

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.