Product Safety - Evaporative Emission Canister Fuel Leakage

General Motors has decided that a defect which relates to motor vehicle safety exists in certain 1996-1997 Chevrolet and GMC passenger and cargo G Vans equipped with gasoline engines. Some of these vehicles may have a fuel-tank, front, rollover valve that could stick open and allow fuel leakage during a certain set of circumstances. If one of these vehicles is parked facing down a grade of 2.5 degrees or more, and the valve sticks open, and if the fuel tank is full or nearly full so that the fuel in the tank submerges the front rollover valve, fuel will leak into the evaporative emission canister until the fuel level in the tank no longer submerges the rollover valve. If the fuel leakage exceeds the canister's capacity, the excess fuel will leak from the fresh air port of the canister onto the ground. If this were to occur, the operator would notice a strong fuel smell after parking the vehicle following a fuel fill. The operator may also notice some dampness on the ground. If a sufficient amount of fuel were to leak out and if an ignition source were present, a vehicle fire could occur.

Dealers are to install a revised evaporative emission pipe assembly.

Involved are certain 1996-1997 Chevrolet and GMC passenger and cargo G vans equipped with a gasoline engine and built within these VIN breakpoints:

Important: Dealers should confirm vehicle eligibility through GMVIS (GM Vehicle Inquiry System) or GM Access Screen (Canada only) or DCS Screen 445 (IPC Only) before beginning campaign repairs. [Not all vehicles within the above breakpoints may be involved.]

Involved vehicles have been identified by Vehicle Identification Number. Computer listings containing the complete Vehicle Identification 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 listings may contain customer names and addresses obtained from Motor Vehicle Registration Records. The use of such motor vehicle registration data for any other purpose is a violation of law in several states/provinces/countries. Accordingly, you are urged to limit the use of this listing to the follow-up necessary to complete this campaign.

Parts required to complete this campaign are to be obtained from General Motors Service Parts Operations (GMSPO). Please refer to your "involved vehicles listing" before ordering parts. Normal orders should be placed on a DRO = Daily Replenishment Order. In an emergency situation, parts should be ordered on a CSO = Customer Special Order.

1. Disconnect the negative battery cable.
2. Following the applicable service manual procedure, relieve the fuel system pressure and drain the fuel tank.
3. Raise and suitably support the vehicle.
4. Loosen the clamp that secures the filler neck hose to the fuel tank, and disconnect the hose from the tank.
5. Disconnect the fuel system electrical harness connector.
6. Disconnect the fuel feed, return and the evaporative emission pipes located in the area of the fuel filter.
7. Install a jack underneath the fuel tank that is suitably for lowering the fuel tank.
8. Remove and discard the fuel tank retaining strap bolts and nuts, and lower the fuel tank.
9. Remove and discard the plastic straps that secure the fuel tank shield to the fuel tank.
10. Disconnect the EVAP emission pipe assembly from the fuel vapor canister, and remove the metallic clamps holding the EVAP emission pipe assembly to the fuel tank along the outboard tank seam flange.
11. Clean the surface of the fuel tank around both of the rollover valves.
12. Remove both rollover valves by lightly pressing down and rotating the valves counterclockwise a quarter of a turn. Discard the removed EVAP emission pipe assembly.
13. Route the new EVAP emission pipe assembly along the opposite side (inboard side) of the fuel tank from where the original assembly was removed.
14. Insert the rollover valves into the openings in the fuel tank and lock them into position by rotating clockwise a quarter of a turn.
15. Secure the new EVAP emission pipe assembly to the fuel tank by slipping the metallic clamps that are attached to the assembly onto the inboard tank seam flange.
16. Connect the new EVAP emission pipe assembly to the fuel vapor canister.
17. Position and raise the fuel tank up to the underbody of the vehicle.
18. Install the fuel filler neck hose to the fuel tank.

Important: When removing or replacing the fuel tank, the fuel tank support fasteners should never be reused. Always use new fasteners when installing the fuel tank.

19. Position the fuel tank straps, and hand start the new fuel tank retaining strap bolts and nuts.

Important: Tighten the strap fasteners by steps, alternating between the fasteners, until the specified torque is reached. A failure to tighten the strap fasteners as specified will cause the bottom of the tank to flex upward. This will result in the fuel gauge indicating that there is fuel remaining in the tank when the tank is empty.

20. Tighten the fuel tank retaining strap bolts.

Tighten
Tighten the bolts to 20.5 N·m (15 lb ft).

Important: The fuel tank filler neck clamps must be properly positioned and aligned. Otherwise, the filler neck may become disconnected from the fuel tank.

21. Position the clamp on the filler neck hose.

Tighten
Tighten the clamp to 2.75 N·m (24 lb in).

22. Connect the fuel feed, return, and evaporative emission pipes.
23. Connect the fuel system electrical harness connector.
24. Lower the vehicle and refill the fuel tank.
25. Connect the negative battery cable.
26. Inspect for fuel leaks.
27. Install the GM Campaign Identification Label.

FOR US AND IPC

Place a Campaign Identification Label on each vehicle corrected in accordance with the instructions outlined in this Product Campaign Bulletin. 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.

Put the Campaign Identification Label on a clean and dry surface of the radiator core support in an area that will be visible to people servicing the vehicle. When installing the Campaign Identification Label, be sure to pull the tab to allow the adhesion of the clear protective covering. Additional Campaign Identification Labels for US dealers can be obtained from Dealer Support Material by calling 1-888-549-6152 (Monday-Friday, 8:00 am to 5:00 pm EST). Ask for Item Number S-1015 when ordering.

Additional Campaign Identification Labels for IPC dealers can be obtained from your Regional Marketing Office.

FOR CANADA

Place a Campaign Identification Label on each vehicle corrected in accordance with the instructions outlined in this Product Campaign Bulletin. 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.

Put the Campaign Identification Label on a clean and dry surface of the radiator core support in an area that will be visible to people servicing the vehicle. Additional Campaign Identification Labels for Canadian dealers can be obtained from DGN by calling 1-800-668-5539 (Monday-Friday, 8:00 am to 5:00 pm EST). Ask for Item Number GMP 91 when ordering.

Submit a Product Campaign Claim with the information indicated below:

Refer to the General Motors WINS Claims Processing Manual for details on Product Campaign Claim Submission.

FOR US AND CANADA

Customers will be notified of this campaign on their vehicles by General Motors (see copy of customer letter included with this bulletin).

FOR IPC

Letters will be sent to known owners of record located within areas covered by the US National Traffic and Motor Vehicle Safety Act. For owners outside these areas, dealers should notify customers using the attached suggested dealer letter.

FOR US AND IPC (US States, Territories, and Possessions)

The US National Traffic and Motor Vehicle Safety Act provides that each vehicle which is subject to a recall campaign of this type must be adequately repaired within a reasonable time after the customer has tendered it for repair. A failure to repair within sixty days after tender of a vehicle is prima facie evidence of failure to repair within a reasonable time. If the condition is not adequately repaired within a reasonable time, the customer may be entitled to an identical or reasonably equivalent vehicle at no charge or to a refund of the purchase price less a reasonable allowance for depreciation. To avoid having to provide these burdensome remedies, every effort must be made to promptly schedule an appointment with each customer and to repair their vehicle as soon as possible. In the recall campaign notification letters, customers are told how to contact the US National Highway Traffic Safety Administration if the campaign is not completed within a reasonable time.

FOR ALL

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 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.

Dear General Motors Customer:

This notice is sent to you in accordance with the requirements of the National Traffic and Motor Vehicle Safety Act.

General Motors has decided that a defect which relates to motor vehicle safety exists in certain 1996-1997 Chevrolet and GMC passenger and cargo Express/Savana vans equipped with gasoline engines. Some of these vehicles may have a fuel-tank, front, rollover valve that could stick open and allow fuel leakage during a certain set of circumstances. If one of these vehicles is parked facing down a grade of 2.5 degrees or more, and the valve sticks open, and if the fuel tank is full or nearly full so that the fuel in the tank submerges the front rollover valve, fuel will leak into the evaporative emission canister until the fuel level in the tank no longer submerges the rollover valve. If the fuel leakage exceeds the canister's capacity, the excess fuel will leak from the fresh air port of the canister onto the ground. If this were to occur, the operator would notice a strong fuel smell after parking the vehicle following a fuel fill. The operator may also notice some dampness on the ground. If a sufficient amount of fuel were to leak out and if an ignition source were present, a vehicle fire could occur.

Your dealer will install a revised evaporative emission pipe assembly on your vehicle. This service will be performed for you at no charge .

The length of time required to perform this service correction is approximately one hour and fifty minutes. Additional time may be required to schedule and process your vehicle. If you dealer has a large number of vehicles awaiting service, this additional time may be significant. Please ask your dealer if you wish to know how much additional time will be needed to schedule, process and repair your vehicle.

Please contact your dealer as soon as possible to arrange a service date. Parts are available and instructions for making this correction have been sent to your dealer.

Your dealer is best equipped to obtain parts and provide services to correct your vehicle as promptly as possible. Should your dealer be unable to schedule a service date within a reasonable time, you should contact the appropriate Customer Assistance Center at the number listed below:

If, after contacting the appropriate customer assistance center, you are still not satisfied that we have done our best to remedy this condition without charge and within a reasonable time, you may wish to write the Administrator, National Highway Traffic Safety Administration, 400 Seventh Street SW, Washington, DC 20590 or call 1-888-327-4236.

The attached customer reply card identifies your vehicle. Presentation of this card to your dealer will assist in making the necessary correction in the shortest possible time. If you no longer own this vehicle, please let us know by completing the attached and mailing it in the postage paid envelope.

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

General Motors Corporation

Enclosure