CAMPAIGN: UPPER INTAKE MANIFOLD GASKET DISTORTION
SUBJECT: 96047 - UPPER INTAKE MANIFOLD GASKET DISTORTION -----------------------------------------------
MODELS: 1996 C,K,P,G TRUCKS EQUIPPED WITH 7.4L (L29) ENGINES ----------------------------------------------------
THIS BULLETIN CANCELS AND REPLACES 96-C-35 ISSUED JULY, 1996. THE "VEHICLES INVOLVED" HAVE BEEN EXPANDED AND THE "CLAIM INFORMATION" TABLE HAS BEEN AMENDED TO INCLUDE G VEHICLES FOR APPROPRIATE LABOR TIME. THE REVISED INFORMATION IS SHOWN IN BOLD AND ITALIC TYPE.
General Motors has decided that CERTAIN 1996 C,K,P,G truck model vehicles equipped with 7.4L engines (RPO L29 - VIN Engine Code J) may exhibit a condition in which the upper intake manifold gaskets do not properly seal between the upper and lower intake manifolds. When this condition occurs, there may be unmetered air pulled into the upper intake manifold causing complaints of rough idle, hesitation, hissing noise, engine stalling and/or a Malfunction Indicator Light (MIL).
To prevent the possibility of this condition occurring, dealers are to replace the upper intake manifold gaskets and apply GM Threadlocker Loctite 272 to the upper manifold bolts.
VEHICLES INVOLVED
Involved are certain 1996 C,K,P,G truck model vehicles equipped with 7.4L engines (RPO L29 - VIN Engine Code J) and built within the following VIN breakpoints:
PLANT YEAR DIVISION MODEL PLANT CODE FROM THROUGH ---- --------- ----- ----- ---- ---- ------- 1996 Chevrolet C,K Pontiac East "E" SOP TE269621 1996 Chevrolet C,K Fort Wayne "Z" SOP TZ226327 1996 Chevrolet C,K Flint "F" SOP TF021343 1996 Chevrolet C,K Janesville "J" SOP TJ416264 Suburban 1996 Chevrolet C,K Janesville "J" SOP TJ112434 JD3500 1996 Chevrolet C,K Silao "G" SOP TG162660 1996 Chevrolet P Detroit "3" SOP T3315059 1996 Chevrolet G Wentzville "1" SOP T1030315 1996 GMC C,K Pontiac East "E" SOP TE555522 1996 GMC C,K Fort Wayne "Z" SOP TZ542972 1996 GMC C,K Flint "F" SOP TF023100 1996 GMC C,K Janesville "J" SOP TJ752276 Suburban 1996 GMC C,K Janesville "J" SOP TJ517559 HD3500 1996 GMC C,K Silao "G" SOP TG520166 1996 GMC G Wentzville "1" SOP T1029853
NOTICE:
Dealers should confirm vehicle elibibility through VISS (Vehicle Information Service System) or ServiceNet (GMC only) prior to beginning campaign repairs. (Not all vehicles within the above breakpoints may be involved).
Involved behicles have been identified by Vehicle Identification Number. Computer listings containing the complete Vehicle Identificatihon Number, customer name and address data have been prepared, and are being furnished to involved dealers with the campaign bulletin. The Customer name and address data furnished will enable dealers to follow-up with customers involved in this campaign. Any dealer not receiving a computer listing with the campaign bulletin has no involved vehicles currently assigned.
These dealer listing may contain customer 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 the follow-up necessary to complete this campaign.
PARTS INFORMATION
Parts required to complete This campaign are to be otbained from General Motors Service Parts Operations (GMSPO). Please refer to your "involved vehicles listing" prior to ordering requirements. Normal orders should be placed on a DRO = Daily Replenishment Order. An emergency requirement should be ordered on a CSO = Customer Special Order
Part Quantity/ Number Description Vehilce ------ ----------- --------- 12534215 Gasket Kit, Upper Intake Manifold 1 12345493 Threadlocker Loctite 272 (Red) 3 ml
NOTICE: Threadlocker Loctite 272 (p/n 12345493) comes in 10 ml container and is sufficient to coat bolts for approximately 3 vehicles.
CUSTOMER NOTIFICATION
Customers will be notified of this campaign on their vehicles by General Motors (see copy of divisional customer letter(s) included with this bulletin).
DEALER CAMPAIGN RESPONSIBILITY
All unsold new vehicles in dealers' possession and subject to this campaign must be held and inspected/repaired per the service procedure of this campaign bulletin before customers take possession of these vehicles.
Dealers are to service all vehicles subject to this campaign at no charge to customers, regardless of mileage, age of vehicle, or ownership, from this time forward.
Customers who have recently purchased vehicles sold from your vehicle inventory, and for which there is no customer information indicated on the dealer listing, are to be contacted by the dealer. Arrangements are to be made to make the required correction according to the instructions contained in this bulletin. This could be done by mailing to such customers a copy of the appropriate divisional customer letter accompanying this bulletin. Campaign follow-up cards should not be used for this purpose, since the customer may not as yet have received the notification letter.
In summary, whenever a vehicle subject to this campaign enters your vehicle inventory, or is in your dealership for service in the future, please take the steps necessary to be sure the campaign correction has been made before selling or releasing the vehicle.
SERVICE PROCEDURE
1. Note settings of all electrical devices and then disconnect negative battery cable.
2. Remove air intake assembly.
3. Remove throttle cable end from throttle body.
4. Remove throttle cable from bracket and move aside.
5. Remove left front and left rear wire harness brackets.
6. Remove right front and right rear wire harness brackets.
7. Remove ignition coil from intake manifold.
8. Remove purge and PCV hoses.
9. Remove EGR pipe from adapter on upper intake manifold.
10. Disconnect all electrical connectors on components attached to upper intake manifold.
11. Remove (8) upper intake manifold bolts.
12. Remove upper intake manifold.
13. Remove the upper intake manifold gaskets and clean sealing surfaces with scraper as needed (Notice, use care when cleaning not to damage sealing surfaces with scrapers or other tools.)
14. Install new upper intake manifold gaskets from kit P/N 12534215 onto lower intake manifold.
15. Install upper intake manifold.
16. Coat the (8) upper intake manifold bolts a minimum of 8 lower threads of each bolt with Loctite 272 (GM P/N 12345493).
17. Install coated bolts in revised tightening sequence (see figure 1) to torque of 8 Nm (6 lb. ft.).
18. Retorque all bolts in sequence to 14 Nm (10 lb. ft.).
19. Connect all electrical connectors to components attached to upper intake manifold.
20. Install ignition coil to intake manifold.
21. Install right rear and front wire harness brackets.
22. Install left rear and front wire harness brackets.
23. Install EGR pipe to adapter.
24. Install purge and PCV hoses.
25. Install throttle cable to bracket.
26. Install throttle cable end to throttle body.
27. Install air intake assembly and torque clamps to 15 Nm (1 1 lb. ft.).
28. Connect Negative battery cable. Start and run engine one minute to verify engine operation (no Malfunction Indicator Lamp illumination).
29. Reset all electrical devices as noted in step 1.
30. Install the GM Campaign Identification Label.
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 the five (5) digit dealer code of the dealer performing the campaign service. This information may be inserted with a typewriter or a ball point pen.
Each "Campaign Identification Label" is to be located o lator core support in an area which will be visible when the vehicle is brought in by the customer for periodic servicing. When installing the Campaign Identification Label, be sure to install the clear protective covering. Additional Campaign Identification.
Labels can be obtained from VISPAC Incorporated by calling 1-800-269-5100 (Monday-Friday, 8:00 a.m. to 4:30 p.m. EST). Ask for Item Number S-1015 when ordering.
Apply the "Campaign Identification Label" only on a clean, dry surface.
CLAIM INFORMATION
Submit a Product Campaign Claim with the information indicated below:
* REPAIR PART FAILED PARTS LABOR LABOR NET PERFORMED COUNT PART NO. ALLOW CC-FC 0P HOURS ITEM
a) Replace Upper Intake Manifold 2 12534215 ** MA-96 IV9941 1.4 *** Gaskets-C,K Truck
b) Replace Upper Intake Manifold 1.8 *** Gaskets-P,G Truck
* For Campaign Administrative Allowance. add 0.1 hours to the "Labor Hours"
** The "Parts Allowance" should be the sum total of the current GMSPO Dealer Net price plus 40% for the gasket kit needed to complete the repair.
*** The amount identifed in the "Net Item" column should represent the sum total of the Current GMSPO Dealer Net Price plus 40% for 3 ml of GM Threadlocker Loctite 272 needed to perform the required repairs.
Refer to the General Motors Corporation Claims Processing Manual for details on Product Campaign Claim Submission.
September 1996
Dear GM Customer,
This notice is sent to inform you that General Motors is conducting a recall campaign that includes your vehicle.
General Motors has decided that certain 1996 C,K, P trucks and G-vans equipped with 7.4L engines (RPO L29 - Engine Code J) may have a condition where the upper intake manifold gasket does not properly seal between the upper and lower intake manifolds. When this condition occurs, there may be unmetered air pulled into the upper intake manifold that could cause rough engine idle, hesitations, hissing noise, engine stalling and/or the illumination of the Malfunction Indicator Lamp (MIL).
To prevent this condition from occurring, your GM dealer will replace the upper manifold gaskets. This service will be performed for you at no charge.
Please contact your GM dealer as soon as possible to arrange a service date and so the dealer may order the necessary parts for the repair. Instructions for making this correction have been sent to your dealer and parts are available. The labor time necessary to perform this service correction is approximately 90 minutes. Please ask your dealer if you wish to know how much additional time will be needed to schedule and process your vehicle.
Your GM dealer is best equipped to obtain parts and provide service to ensure that your vehicle is corrected as promptly as possible. If, however, you take your vehicle to your dealer on the agreed service date, and they do not remedy this condition on that date or within five (5) days, we recommend you contact the Chevrolet Customer Assistance Center by calling 1-800-222-1020 or GMC Consumer Relations office. The telephone number of the Consumer Relations office is listed in your Warranty and Owner Assistance Information Manual.
The enclosed owner reply card identifies your vehicle. Presentation of this card to your dealer will as r rra ing the necessary inspection/correction in the shorlest possible time. If you have sold or traded your vehicle, please let us know by completing the postage paid reply card and returning it to us. We are sorry to cause you this inconvenience; however, we have taken this action in the interest of your continued satisfaction with our products.
GENERAL MOTORS CORPORATION
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.
