HIGH ACCELERATOR PEDAL EFFORT INOPERATIVE CRUISE CONTROL
MODELS AFFECTED: 1987-88 CENTURYS AND 1988 REGALS WITH 2.8L V-6 ENGINES (VIN CODE W)
This bulletin has been revised to add an additional statement in the "Important" notice after Step 11.
This bulletin updates Buick Bulletin 88-9-10 dated 02-03-89.
Condition
Some customers may comment about high accelerator pedal operating efforts and/or inoperative cruise control system on 1987-88 Centurys or 1988 Regal models with 2.8L V6 engine (VIN Code W).
Cause
The high effort or loss of cruise may be attributed to a wear condition in the throttle body actuating linkage. This condition may be repaired by replacing the throttle body actuating linkage using components in the service kit. The following procedure should be used to replace the components.
Procedure (Reference Figure #1)
1. Place vehicle in park. Set parking brake and disconnect negative battery cable.
2. Disconnect throttle valve (T.V.), accelerator, and cruise control cables from the throttle body.
3. Remove the circular "E" clip (Figure #1, Item #1) from the throttle actuating link stud of the throttle lever (Item #12).
4. Using a T40 Torx Bit, rotate the throttle actuating lever screw (Item #3) CLOCKWISE to remove it from the throttle body.
CAUTION:
Keep fingers clear of throttle actuating lever. Springs are under tension and will unwind when tension is released. Springs may become detached and cause injury. Wear safety glasses.
IMPORTANT: Left hand threads on screw.
If breakage of the screw occurs, replace the throttle body assembly.
All parts removed, per this bulletin, should be forwarded per the instructions in the warranty parts return program. If a parts return program is not applicable, then the parts may be scrapped.
5. Remove the throttle actuating lever and bushing assembly (Item #4), thrust washers, spring pack retainers, and springs.
6. Using compressed air, clean threads in throttle body casting and replacement screw.
7. Install the throttle body service linkage kit (with rubber band still in place) to the throttle body assembly by hand tightening (left hand threads) the throttle actuating lever screw in a COUNTERCLOCKWISE direction.
8. Position the casting side pawl (Item #5) in the semicircular groove (Item #10), and the lever side pawl (Item #6) in the notch area of the throttle actuating lever.
9. Install the throttle actuating link (Item #2) to the throttle lever stud using a new "E" clip.
10. Cut and remove the rubber band (Item #11).
IMPORTANT: Do not remove the spring pack retainer (Item 9).
11. Recheck the position of the pawls, check freedom of movement of linkage, then torque the throttle actuating lever screw to 10-12 lb-ft (14-16 Nm.).
IMPORTANT: Do Not Overtorque
If after throttle actuating screw is properly torqued, it appears loose, entire throttle body is to be replaced.
12. Remove spring pack retainer by pulling on tab.
13. In accordance with instructions in Service Manual Section 6C, when performing service on accelerator controls, inspect the linkage and cables for binding, interference with other components or physical damage (kinks, burns, etc.):
- Grasp accelerator cable terminal, and move it in and out. Cable should move freely with no binding or sticking.
- Pull cable out and release the terminal. Due to pedal weight, the cable should return to its fully retracted position without delay.
- If required, replace cable per Service Manual Section 6C.
14. Install the throttle valve (T.V.), cruise control, and accelerator cables.
15. Adjust T.V. cable and cruise control cable, per the procedures in Service Manual Sections 7A and 9B, respectively.
16. Check linkage operation prior to starting engine by actuating accelerator pedal several times throughout its full range:
With the aid of an underhood observer or diagnostic scanner such as a Tech 1, check to ensure that the throttle lever reaches full "wide-open" upon fully depressing the pedal and that it returns to the idle position without delay upon releasing the pedal.
Throttle should operate smoothly with no binding or sticking. Pedal operating efforts required to reach full throttle should not be excessive.
If operation is unsatisfactory, repair or replace other linkage components (pedal, cables, etc.) as required, per the Service Manual procedures.
NOTICE: Do not attempt to use lubricant on cables, internal damage may result. Unsatisfactory operation is to be corrected by cable replacement only.
THROTTLE BODY SERVICE LINKAGE KIT
* KIT PART NUMBER ---------------- MODEL YEAR MODEL YEAR ----------- ---------- BODY 1987 1988 ---- ---- ----
Century 17112173 17112175
Regal N/A 17112175
* Kit will include: Throttle Actuating Lever and Link Assembly Spring Pack 1 Steel Thrust Washer I Nylon Thrust Washer Screw (Left Hand Threads) E-Clip Spring Pack Clip Rubber Band Retainer
Parts are currently available from GMSPO.
WARRANTY INFORMATION
Labor Operation Number: T1396 Labor Time: Auto. Carline Trans. ------- ----- A .4 Hours Trouble Code: 92 W .5 Hours
If necessary to replace accelerator pedal or any cable, use the applicable labor operation and time per the Labor Time Guide.
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.
