General Motors of Canada has determined that a defect which relates to motor vehicle safety exists in some 1984 through 1988 Chevrolet, Pontiac, Oldsmobile, Buick and Cadillac model vehicles equipped with cruise control on certain gasoline and diesel engines. A small nylon bushing in the cruise control servo bail (bracket) may slip out of place. This will not affect the operation of the cruise control, but it may cause intermittent increases in engine speed or dieseling (engine run-on with ignition off). If the vehicle is not serviced and the nylon bushing remains out of place, the servo rod assembly could wear through the bail. If the rod wears through the bail, it may catch on other engine components and possibly result in a stuck throttle. Although the vehicle can still be stopped with the service brake, an unexpected loss of accelerator control could result in a vehicle crash.
To prevent this condition from occurring, dealers are to install a Bushing Kit on the Cruise Control Servo Bail. The cruise control servo assembly is not authorized as a replacement to correct for a missing or out of place bushing. Also, if other repairs are needed to the cruise control system, and the vehicle is out of warranty, the repair would be at the owner's expense.
Certain 1984 through 1987 vehicles equipped with Cruise Control (RPO K34) and engines as listed below, and certain 1988 vehicles equipped with Cruise Control (RPO K34) and 5.0L engine within the breakpoints listed below:
YEAR DIVISION MODEL FROM THROUGH ---- -------- ----- ---- ------- 1984 CHEVROLET Caprice SOP EOP Monte Carlo SOP EOP PONTIAC Parisienne SOP EOP Bonneville/Grand Prix SOP EOP OLDSMOBILE Delta 88/Custom Cruiser SOP EOP 98 Regency SOP EOP Toronado SOP EOP Cutlass Supreme SOP EOP BUICK LeSabre/Estate Wagon SOP EOP Electra/Park Avenue SOP EOP Riviera SOP EOP Regal SOP EOP CADILLAC Fleetwood Brougham SOP EOP Eldorado SOP EOP Seville SOP EOP
1985 CHEVROLET Caprice SOP EOP PONTIAC Parisienne SOP EOP OLDSMOBILE Delta 88/Custom Cruiser SOP EOP Toronado SOP EOP Cutlass Supreme SOP EOP BUICK LeSabre/Estate Wagon SOP EOP Riviera SOP EOP CADILLAC Fleetwood Brougham SOP EOP Eldorado SOP EOP Seville SOP EOP
1986 CHEVROLET Caprice SOP EOP PONTIAC Parisienne SOP EOP OLDSMOBILE Custom Cruiser SOP EOP Cutlass Supreme SOP EOP BUICK Regal SOP EOP LeSabre/Estate Wagon SOP EOP CADILLAC Fleetwood Brougham SOP EOP
1987 CHEVROLET Caprice SOP EOP PONTIAC Parisienne SOP EOP OLDSMOBILE Custom Cruiser SOP EOP Cutlass Supreme SOP EOP BUICK LeSabre/Estate Wagon SOP EOP Regal SOP EOP CADILLAC Fleetwood Brougham SOP EOP
1988 CHEVROLET Arlington Caprice SOP JR156982 Lakewood Caprice SOP JA147249 PONTIAC Lakewood Parisienne SOP JA202810 OLDSMOBILE Arlington Custom Cruiser SOP JR306803 Pontiac Plant Cutlass Supreme SOP EOP BUICK Lakewood Electra Estate Wagon SOP JA404650 CADILLAC Detroit Fleetwood Brougham SOP J9735104 Arlington Fleetwood Brougham JR750001 JR751072
Vehicles with Part Number 25074629 or Part Number 12335036 replacement Cruise control Servos do not require the Bushing Kit called for in this Product Campaign Bulletin. Those vehicles must be identified by inspection.
All affected vehicles have been identified by the VIN listing provided to involved dealers with this bulletin. Any dealer not receiving a listing was not shipped any of the affected vehicles.
Dealers are to service all vehicles subject to this campaign at no charge to owners, regardless of mileage, age of vehicle, or ownership, from this time forward.
Whenever a vehicle subject to this campaign is taken into your new or used vehicle inventory, or it is in your dealership for service in the future, you should take the steps necessary to be sure the campaign correction has been made before reselling or releasing the vehicle.
Owners of vehicles recently sold from your new vehicle inventory are to be contacted by the dealer, and arrangements made to make the required modification according to instructions contained in this bulletin.
Refer to Section 4 of the Service Policies and Procedures Manual for the detailed procedure on handling Product Campaigns. Dealers are requested to complete the campaign on all transfers as soon as possible.
All owners of record at the time of campaign release are shown on the attached computer listing and have been notified by first class mail from General Motors. The listings provided are for campaign activity only and should not be used for any other purpose.
Parts required to complete this campaign should be ordered throuqh regular channels, as follows:
DESCRIPTION PART NUMBER QUANTITY PER VEHICLE ----------- ----------- -------------------- Bushing Kit 25111444 1
Credit for the campaign work performed will be paid upon receipt of a properly completed campaign claim card, RAPID terminal or DCS transmission in accordance with the following:
Repair Code Description Time Allowance ----------- ----------- --------------- 1A Inspect Cruise Control Servo Bail Only .3
2A Inspect Cruise Control Bail and Install .3 Bushing Kit
Time allowance includes 0.1 hour for dealer administrative detail associated with this campaign. Parts credit will be based on dealer net plus 30% to cover parts handling.
1. Raise hood and install a fender cover on the left fender.
2. Examine the Cruise Control Servo. If the Bushing in the Bail of the Servo looks like it was formed in place (a permanent part of the Bail Assembly - see Figure 1), go directly to Step (12) and install a Campaign Identification Label.
If the Bushing is a "snap-in" bushing (with tabs) as shown in View "B" of Figure 2, continue to Step (3).
3. Disconnect any electrical and hose connections, if necessary, to the air cleaner and remove air cleaner assembly.
4. Before removing the Spring Retainer from its adjustment hole in the Servo Rod Assembly, scribe a mark on the rod next to the hole to identify where the Spring Retainer is to be reinstalled (see Figure 2).
5. Remove the Spring Retainer. Do NOT remove the "Z" pin.
6. Align the "Z" pin with the rod as shown in View "A" of Figure 2, then slide the rod rearward out of the bail (it may also be necessary to slightly collapse the Servo diaphragm and move the Bail forward).
Pinch the Bushing flange with a pair of pliers and remove the Bushing from the Bail. The Bushing may not be in the Bail hole as originally installed; it may be free to move on the Servo Rod Assembly. Remove and discard the old Bushing.
7. If the Servo Bail hole has a burr, file off the burr so that the Bail surface is flat on both sides.
8. Obtain Bushing Kit (P/N 25111444). Install the Bushing onto the Bail as shown in Figure 3, so that the two tabs snap firmly in place. If the bail is bent (or twisted) so that the new Bushing will not easily snap into place on the Bail (as shown in Figure 3), straighten the Bail as necessary.
9. Install the Clip over the Bushing and Bail as shown in Figures 3 and 4. Reinstall the Servo Rod Assembly through the new Bushing by positioning the "Z" pin as shown in View "A" of Figure 2. Reinstall the spring retainer in the original (marked) hole in the rod, pointing the spring retainer in the direction shown in Figure 4.
If the Servo Rod Assembly is missing the "Z" pin, install a second Spring Retainer in the end hole normally occupied by the "Z" pin.
10. Ensure that the throttle mechanism will return fully to the idle position.
11. Reinstall the air cleaner assembly and reconnect hose and electrical connections as may be appropriate.
Clean surface of radiator upper mounting panel and apply a Campaign Identification Label. Make sure the correct campaign number is inserted on the label. This will indicate that the campaign has been completed.
Dear General Motors Customer:
General Motors of Canada has determined that a defect which relates to motor vehicle safety exists in some 1984 through 1988 Chevrolet, Pontiac, Oldsmobile, Buick and Cadillac model vehicles equipped with cruise control on certain gasoline and dieset engines. A small nylon bushing in the cruise control servo bail (bracket) may slip out of place. This will not affect the operation of the cruise control, but it may cause intermittent increases in engine speed or dieseling (engine run-on with ignition off). If the vehicle is not serviced and the nylon bushing remains out of place, the servo rod assembly could wear through the bail. If the rod wears through the bail, it may catch on other engine components and possibly result in a stuck throttle. Although the vehicle can still be stopped with the service brake, an unexpected loss of accelerator control could result in a vehicle crash.
To prevent this condition from occurring on your vehicle, we will install a new bushing in your cruise control servo bail. Even if you or someone else has removed the old bushing, a new design bushing must be installed to prevent the rod in the throttle linkage from wearing through the cruise control servo bail. This service will be performed for you at no charge. The above repair is for bushing replacement only and does not cover other repairs to the cruise control system.
Please contact your GM dealer immediately to arrange a service date. Instructions have been sent to your dealer. The labour time to perform the work is about 15 minutes. Please allow additional time for your dealer to process your vehicle.
This letter identifies your vehicle. Presentation of this letter to your dealer will assist their Service personnel in completing the necessary correction to your vehicle in the shortest possible time. Further assistance, if required, may be obtained from the General Motors Zone Office nearest you.
Your vehicle Owner's Manual provides the location and phone number of each respective Zone Office. We are sorry to cause you this inconvenience; however, we have taken this action in the interest of your continued satisfaction with our products.
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.