Fuel System - Intermittant Hard Start
90chevy15Number: 88-434-6
Section: 6
Date: January 1990
Corp. Bulletin No.: 966303
Subject: INTERMITTANT HARD START OR LONG CRANK
Model and Year: 1987-88 S/T TRUCK
Some 1987-88 S/T pickups may experience a condition where the fuel in the fuel lines drains back into the fuel tank after the vehicle is turned off and not restarted for a period of time, usually overnight or longer. This condition may be caused by a leaking check valve in the in-tank fuel pump. Effective Julian date 1218 (May 1, 1988) a change was made to correct this condition.
If this intermittent hard start or long crank condition cannot be repaired using normal service procedures, a new in-tank fuel pump and strainer may be installed. Refer to section 4 - Fuel Control of the Light Duty Fuel, Driveability and Emissions Service Manual, for fuel pump removal and reinstallation procedures.
Figure 1:
IMPORTANT: When replacement of the fuel pump is necessary, the manufacturing date of the new fuel pump should be checked before installation. The Julian date of the new fuel pump can be found stamped on the side of the fuel pump housing (Figure 1). Only install fuel pumps with a Julian date of 1218 or greater.
Parts Information
P/N Description Quantity Application
25115462 Fuel Pump 1 1987-88 S/T All
25055461 Filter/Strainer 1 1987-88 S/T pick-up W/NK2 (20 gallon tank)
25055458 Filter/Strainer 1 1987-88 S/T pick-up W/0 NK2
Parts are currently available from GMSPO.
For vehicles repaired under warranty, use:
Labor Operation Number: J5590
Use the appropriate time from the labor time guide.