-------- The "Fuel System Pressure Test" procedure located on pages 16 and 17 of the 1991-1992 "Fuel/Air Intake/Exhaust Service Manual" was printed incorrectly. Attached to this bulletin are two stickers. One sticker has a new chart and new steps 3, 4 and 4a., that should be placed on the bottom of page 16. The other sticker, which is blank, should be placed on page 17 over step 10 and the "Important" information steps that follow step 10. (Refer to the following illustration for correct sticker placement.)
SOHC (LKO) Minimum System Pressure: 179 kPa (26 psi) Maximum System Leakdown (in 5 minutes): New Vehicle: 24 kPa (3 psi) max. Service Limit: 34 kPa (5 psi) max.
DOHC (LLO) Minimum System Pressure: 262 kPa (38 psi) Maximum System Leakdown (in 5 minutes): New Vehicle: 20 kPa (3 psi) max. Service Limit: 41 kPa ( psi) max.
3. Install bleed hose into an approved container and open shut-off valve to bleed any fuel in the system.
4. Close the fuel pressure gauge shut-off valve.
a. Turn ignition key to ON position (do not start engine) and record maximum pressure. Cycle the key on and off several times to establish an accurate reading. Allow gauge pressure to stabilize for thirty second. Refer to readings in chart:
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.