SVC. MANUAL UPDATE FUEL SYS. PRESSURE RELIEF(REV. PROCED.)

SUBJECT: SERVICE MANUAL UPDATE-SECTIONS 6A, 6C, 6E FUEL SYSTEMS - PRESSURE RELIEF (REVISED PROCEDURES)

MODELS AFFECTED: 1989-91 SKYLARK MODELS 1989-91 CENTURY MODELS WITH 2.5L ENGINES (VIN CODE R)

This bulletin is revised to include 1989-91 Century models and replaces Service Bulletin 91-6C-1 which may be discarded.

SERVICE MANUAL UPDATE - SECTIONS 6A, 6C, 6E2 AND 6E3

CAUTION:

- TO REDUCE THE RISK OF FIRE AND PERSONAL INJURY, RELIEVE THE FUEL SYSTEM PRESSURE BEFORE SERVICING FUEL SYSTEM COMPONENTS.

- AFTER RELIEVING SYSTEM PRESSURE, A SMALL AMOUNT OF FUEL MAY BE RELEASED WHEN SERVICING FUEL LINES OR CONNECTIONS. TO REDUCE THE CHANCE OF PERSONAL INJURY, COVER FUEL LINE FITTINGS WITH A SHOP TOWEL BEFORE DISCONNECTING, TO CATCH ANY FUEL THAT MAY LEAK OUT. PLACE THE TOWEL IN AN APPROVED CONTAINER WHEN DISCONNECT IS COMPLETED.

FUEL PRESSURE RELIEF PROCEDURE:

1989-91 2.3L (VIN D) and 2.5L (VIN R AND U)

1. Loosen fuel filler cap to relieve tank pressure (Do not tighten at this time).

2. Raise vehicle.

3. Disconnect fuel pump electrical connector.

4. Lower vehicle.

5. Start engine and run until fuel supply remaining in fuel pipes is consumed. Engage starter for 3.0 seconds to assure relief of any remaining pressure.

6. Raise vehicle.

7. Connect fuel pump electrical connector.

8. Lower vehicle.

9. Disconnect negative battery terminal to avoid possible fuel discharge if an accidental attempt is made to start the engine.

3.3L (VIN N)

Tool required: J 34730-1, Fuel Pressure Gage

1. Disconnect negative battery terminal to avoid possible fuel discharge if an accidental attempt is made to start the engine.

2. Loosen fuel filler cap to relieve tank pressure.

3. Connect J 34730-1 to fuel pressure connection. Wrap a shop towel around fitting while connecting gage to avoid spillage.

4. Install bleed hose into an approved container and open valve to bleed system pressure. Fuel connections are now safe for servicing.

5. Drain any fuel remaining in gage into an approved container.

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.