EXPERTEC TSB (91E14)

EXPERTEC TSB

TECHNICAL SERVICE BULLETIN

CAMPAIGN: LOW (TPS) OUTPUT - (INSPECT/REPLACE TPS SWITCH)

Model(s): 1991 GMC C, K, R, V, P Trucks and G-Vans

Bulletin No.: GMC 91E14

Date: 08/12/1991

SERVICE INFORMATION

General Motors has determined that certain 1991 C, K, R, V, P trucks and G-Vans with 4.3L, 5.7L, or 7.4L fuel-injected gasoline engines, coupled with the Hydra-Matic 4L80-E electronic transmission (MT1), may have a TPS that exhibits an intermittent low output voltage. This condition may cause no upshift to 4th gear, no TCC, or harsh transmission shifts.

To correct this condition dealers will inspect, and if necessary, replace the TPS switch.

VEHICLES INVOLVED

Involved are certain 1991 C, K, R, V, P trucks and G-Vans with 4.3L, 5.7L, or 7.4L fuel-injected gasoline engines, coupled with the Hydra-Matic 4L80-E electronic transmission (MT1) built within the following VIN breakpoints:

Model	Make	Plant	From	Through
C/K	GMC	Pontiac East Oshawa Janesville	SOP	ME534777 M1541745 MJ519682
RN	GMC	Flint	SOP	MF520807
P	GMC	Detroit	SOP	M3501970
G	GMC	---	---	M7512706 M4512352

The specific vehicles involved in this campaign have been identified by Vehicle Identification Number Computer Listings. These listings are furnished to all involved dealers with the campaign bulletin.

DEALER CAMPAIGN RESPONSIBILITY

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. Dealers are to correct all affected vehicles in new and used vehicle stock prior to their sale.

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 ensure 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 correction according to instructions contained in this bulletin. If the name and address of the owner of an involved vehicle was unavailable to GMC Truck Division at the time of campaign initiation, the dealer must determine the owner's name and address from the dealership sales records. Please provide this information directly on the second copy of the listing next to the applicable VIN so that our records may be updated and the appropriate notification mailed to the owner. This second copy should then be submitted to the address listed below in the previously supplied yellow campaign envelopes.

GMC Truck Division

General Motors Corporation

101 Union Street

Plymouth, Michigan 48170

OWNER NOTIFICATION

Owners will be notified of this campaign on their vehicles by GMC Truck Division (see copy of owner letter included with this bulletin). A listing of owner names and addresses has been furnished to the involved dealers to enable dealers to follow up with owners involved in this campaign. This listing may contain owner names and addresses obtained from State Motor Vehicle Registration records. The use of such motor vehicle registration data for any other purpose is a violation of law in several states. Accordingly, you are urged to limit the use of this listing to this campaign.

SERVICE INFORMATION

A new TPS Kit (P/N 17112679) has been released to address the complaint conditions. The new TPS will have a yellow dot at the connector area for easier identification.

SERVICE PROCEDURE

1. Remove air cleaner, if necessary.
2. Inspect vehicle's TPS for a yellow dot. If the TPS has a yellow dot at the connector area, no further action is necessary. Install "Campaign Identification Label."
3. If the TPS does not have a yellow dot, replace TPS with the new TPS Kit (P/N 17112679). Follow procedures in the 1991 Light-Duty Truck Fuel and Emissions Service Manual, X-9136, Page 3-206.
4. Install "Campaign Identification Label".

PARTS INFORMATION

Parts are to be obtained from General Motors Service Parts Operation (GMSPO).

To ensure that these parts will be obtained as soon as possible, they should be ordered from GMSPO on a C.I.O. order with no special instruction code but order under an advise code (2).

Part Number	Description	Quantity
17112679	TPS Kit	1

WARRANTY INFORMATION

Dealers should submit a warranty claim on each vehicle completed under this campaign.

Labor Operation Number	Description	((1)  ) Time Allowance	Trouble Code
V6830	TPS-R & R (C/K, R/V)	.5 Hr.	96
V6831	TPS-R & R (G/P)	.6 Hr.	96
V6832	TPS-Inspect. No further action required.	.2 Hr.	96
V6833	TPS-inspect. No further action required. (G/P)	.4 Hr.	96
(1) For dealer to receive Administrative Time Allowance associated with this campaign, add 0.1 hour to the labor Operation Time Allowance.

CAMPAIGN IDENTIFICATION LABEL

Each vehicle corrected in accordance with the instructions outlined in this Product Campaign Bulletin will require a "Campaign Identification Label."

Each label provides a space to include the campaign number and five (5) digit dealer code of the dealer performing the campaign service. This information may be inserted with a typewriter or ball point pen. Each "Campaign Identification Label" is to be located on the radiator core support in an area which will be visible when the vehicle is brought in for periodic servicing by the owner. Apply "Campaign Identification Label" only on a clean, dry surface.

ADMINISTRATIVE PROCEDURE

Procedures covering this campaign are outlined in Section V of your dealership's"GM Truck Claims Processing Manual" #P9119.

CUSTOMER NOTIFICATION LETTER OF CAMPAIGN

Dear GMC Truck Owner:

General Motors has determined that the throttle position sensor (TPS) on certain 1991 C, K, R, V, P trucks and G-Vans may exhibit an intermittent low-output voltage. This condition may cause the transmission to have no overdrive and/or harsh transmission shifts.

To correct this condition, the existing TPS will be replaced with a new updated part. This service will be completed for you at no charge.

Instructions for making this correction have been sent to your GMC Truck dealer. Please contact your dealer as soon as possible to arrange a service date. Please ask your dealer if you wish to know how much time will be needed to schedule, process and repair your vehicle. Your GMC Truck dealer is best equipped to provide service to ensure your vehicle is corrected as promptly as possible. However, if you take your vehicle to your dealer on the agreed service date and they do not service this condition on that date or within five days, we recommend you contact your nearest GMC Truck Zone Office by telephone. The Zone Office will assist you and your dealer in getting your vehicle corrected. The telephone numbers of the Zone Offices are listed in your Warranty and Owner Assistance Information Manual.

After contacting your GMC Truck dealer and the Zone Office, it you are still not satisfied that we have done our best to remedy this condition without charge within a reasonable time, you may wish to write the Environmental Protection Division (EN-340F), United States Environmental Protection Agency, 401 M Street, S.W., Washington, D.C. 20460. To ensure your full protection under the emission warranty made applicable to your vehicle by Federal Law, and your right to participate in future recalls, it is recommended that you have your vehicle serviced as soon as possible. Failure to do so could legally be determined to be lack of proper maintenance of your vehicle. Also, your vehicle may fail a state or local emission inspection test if the recall work is not accomplished.

Should your dealer find that your emission system has been intentionally disabled, you will be asked if you wish the system to be restored so that it will function as designed. The cost of such restoration will be your responsibility.

The enclosed postage paid owner reply card identifies your vehicle.

Presentation of this card to your GMC Truck dealer will assist in making the necessary correction to your vehicle in the shortest possible time. If you have sold or traded your vehicle, please furnish us complete name and address of the person you sold or traded your vehicle to and return the card to us.

We are sorry to cause you this inconvenience; however, we have taken this action in the interest of your continued satisfaction.