Century Estate Wagon V6-231 3.8L (1985)
Shift Modulator: All Technical Service Bulletins
IB. Harsh 3-2 and/or 4-2 Shifts
1985-90 Century, Electra/Park Avenue, Riviera/Reatta, LeSabre and Regal models
Service Procedure:
Harsh 3-2 and 4-2 shifts at any altitude may be caused by a missing or partial hole in the spacer plate. Remove the valve body and inspect the spacer
plate for a missing or partial governor passage hole (25) as shown in Figure 3. A partial hole can be drilled out using a # 77 drill bit to meet the hole size
requirement of .46 mm (.018"). If the hole is missing, use the spacer plate gasket and control valve body as a guide to locate and drill the hole, or replace
the spacer plate.
Figure 3
