Engine - Will Not Start Readily Upon Cranking

File In Section: 6E - Engine Fuel & Emission

Bulletin No.: 56-63-05A

Date: January, 1996

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 M/L (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