VEHICLE DOES NOT START READILY UPON CRANKING

Subject: Vehicle Does Not Start Readily Upon Cranking (Replace Fuel Pump Relay) --------------------------------------------------------------------

Models: 1993-94 Chevrolet and GMC Truck M/L Vans 1994 Chevrolet and GMC Truck S/T Utility 1994 Oldsmobile Bravada with 4.3L Engine (VIN W, Z - RPOs L35, LB4) ---------------------------------------------

This bulletin is being revised to change the correction procedure and parts information and to add the L Van and artwork. Please discard Corporate Bulletin Number 56-63-05 (Section 6E - Engine Fuel & Emission).

CONDITION

Some owners may experience extended engine crank times on cold start and may set diagnostic trouble code 54 and activate the MIL (Check Engine light).

CAUSE

This condition may be due to failure of the fuel pump relay.

CORRECTION

Verify condition using the normal diagnostic procedure in the service manual. Replace the Fuel Pump Relay (P/N 12077867) following the service manual procedure. Replace the connector (Kit P/N 12166225) following the instructions in Figures 3 and 4. Note that each of the four cavities of the old connector are lettered. The new connector is numbered and it should be wired according to Figure 3 and not the instructions contained within the connector kit.

Parts Information

P/N Description Qty --- ------------ ---

12077867 Fuel Pump Relay 1 12166225 Connector 1 12129073 Bracket (S/T Only) 1

Parts are currently available from GMSPO.

Warranty Information

For vehicles repaired under warranty, use:

Labor Operation Description Labor Time --------- ----------- ----------- J5460 Relay, Fuel Pump Use Published Replace Labor Operation Time

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.