Throttle Valve - Buzz Condition
Number 86-7-17 Date 3/86Subject: VALVE BODY THROTTLE VALVE BUZZ, THM 125C TRANSMISSION
1985 AND 1986 PONTIAC VEHICLES EQUIPPED WITH THM 125C TRANSMISSION MODEL CODES 1985: CD, CE, CJ, CK, CL, CT, CU, CX, HS, HV 1986: CDC, CJC, CTC, CUC, CXC
THM 125/125C TRANSMISSION I.D. NAMEPLATE YPSILANTI, MICHIGAN:
THM 125/125C TRANSMISSION I.D. NAMEPLATE WINDSOR, CANADA:
A 1985 or 1986 THM 125C transaxle built prior to October 29, 1985 (Julian date 302) in Windsor, or prior to December 9, 1985 (Julian date 343) in Ypsilanti, may exhibit a throttle valve buzz condition. Refer to above list for model/year applications. All of the models listed are 2.8L engine applications. Refer to Figure 1 for transaxle identification information.
Beginning on the listed dates, a new valve body to case cover spacer plate was introduced to eliminate the buzz by reducing the diameter of the 1-2 accumulator valve feedback orifice.
To correct a throttle valve buzz condition for models built before these dates, replace the original valve body to case cover spacer plate with the new spacer plate (P/N 8660569).
Refer to the appropriate Service Manual for removal and installation procedures.