HIGH IDLE SPEED WHEN COLD CAUSING HARSH SHIFT INTO GEAR
MODELS: 1985 M VAN WITH 4.3L V6 (VIN CODE N) AND AUTOMATIC TRANSMISSIONS
THIS BULLETIN CANCELS AND SUPERCEDES CHEVROLET DEALER SERVICE BULLETIN 85-209 DATED JULY, 1986, ALL COPIES OF WHICH SHOULD BE DESTROYED.
Some 1985 M vans equipped with the 4.3L V6 engine and automatic transmissions may experience harshness when shifting from Park or Neutral into gear. This condition only occurs when the engine is on fast idle (cold engines) and the engine fast idle speed is set at 2200 rpm.
This condition can be improved by lowering the fast idle speed to 1800 rpm. Refer to the vehide emission (tune-up) label for the proper procedure for fast idle adjustment (See Figure No. 1).
Whenever this procedure is performed, it is also necessary to install a new revised fast idle specification label, P/N 10066489, adjacent to the Emission Label (See Figure No. 1).
LABEL INSTALLATION PROCEDURE
1. Locate area where label is to be attached.
2. Clean area where label is to be attached using GM fabric cleaner, P/N 1050244, or GM choke cleaner, P/N 1050494, or equivalents.
3. Position label on fan shroud, as shown, with print in an upright position, readable from the front of the vehide.
If additional labels (P/N 10066489) are required, they can be obtained for a nominal fee from:
Adistra Corporation P.O. Box 56006 Pontiac, MI 48056-9099 Attn: GMC Service Publications
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.
