Dealer Information

C H E V R O L E T B U L L E T I N

Origin No. SER-64
C. O. No. 91-206
Date: September 10, 1991

SUBJECT: PRODUCT EMISSION CAMPAIGN 91C23
THROTTLE POSITION SENSOR


TO: Service & Customer Satisfaction Managers DAC Managers


GOAL: To inspect and correct all units involved as indicated in the attached Emission Campaign Bulletin.


ACTION: Dealers are to inspect and/or repair the vehicles as described in the bulletin.


DUE DATE:
C. O. CONTACT PERSON: R. J. Evanch, Product Campaign Manager, Technical Service Department, 8-227-6595


General Motors has been determined that certain 1991 Chevrolet C/K, R/V & P trucks and-G vans with 4.3L, 5.7L or 7.4L fuel-injected gasoline engines, coupled with Hydra-Matic 4L80 electronic transmissions (MTI), may have a Throttle Position Sensor (TPS) which exhibits intermittent low output voltage. This condition may cause the transmissions in these vehicles to have no upshift to 4th gear, no TCC, or harsh transmission shifts.

To correct this condition, dealers are to inspect and, if necessary replace, the TPS switch according to instructions contained in the bulletin.

Parts required to complete this campaign are to be obtained through General Motors Service Parts Operations (GMSPO).

The attached recap indicates the number of vehicles involved in each Branch.


RECAP 91C23

BRANCH INVOLVED UNITS

2 NEW YORK 2067

3 ST. LOUIS 1052

4 MINNEAPOLIS 2829

5 KANSAS CITY 1643

6 SAN FRANCISCO 2553

7 DALLAS 3183

8 ATLANTA 2197

9 CINCINNATI 2723

10 DENVER 1947

11 CHICAGO 4726

13 PITTSBURGH 1377

14 WASHINGTON 1237

15 PHILADELPHIA 1724

16 CHARLOTTE 1219

17 MEMPHIS 1413

19 PORTLAND 2777

20 LOS ANGELES 7414

26 TAMPA 1601

30 HOUSTON 1902

32 BOSTON 914

44 DETROIT 1756

48 SYRACUSE 1051

CO CONTROLLED 1969

U.S. TOTAL 51274

DOMESTIC (TOTAL ABOVE) 51274
FOREIGN (CANADIAN) 1607
(GMOO/ODC) 1350

TOTAL 54231