Firebird V8-305 5.0L VIN F FI (1987)
Accelerator Pump: All Technical Service Bulletins
Engine - Poor Driveability
Number
87-6 (Gasoline)-90A
Date
6/88
Subject:
DRIVEABILITY: HIGH AMBIENT COLD START DRIVEABILITY
1986-87 SAFARI WAGON, FIREBIRD AND GRAND PRIX MODELS WITH 5.0L ENGINE LG4 (VIN CODE H)
"This bulletin supercedes bulletin 87-6(Gasoline)-90, dated 5188. This bulletin is being revised to delete the word reduced from the title and change the
word reduced to regarding in the first paragraph."
Some 1986-87 passenger cars equipped with LG4 (VIN Code H) engines may experience customer comments regarding driveability during the first few
minutes of operation after startup, following an extended soak (6 hours or more) at relatively high ambient temperatures.
This condition may be the result of leanness during this type of operation. Typical symptoms of leanness are idle roughness and hesitation or sag on
tip-in. In some instances, the condition may be addressed by performing the following service procedures.
Parts Required
1
P/N 17083343 Accelerator pump discharge spring
1
P/N 17083344 Accelerator pump assembly
Service Procedure
A.
Install the new accelerator pump and discharge spring as follows:
1.
Disconnect the negative battery cable.
2.
Remove the air cleaner.
3.
Remove the carburetor air horn. (Refer to Section 6C1 of the Service Manual if details of disassembly are needed.)
4.
Remove the solenoid adjusting screw plug from the airhorn.
5.
Remove the solenoid plunger, air horn gasket, pump assembly, metering rods, and float bowl insert.
6.
Count and record the number of turns to the solenoid adjusting screw to lightly bottom the mixture control solenoid.
7.
Remove the mixture control solenoid assembly.
8.
Remove the float and needle.
9.
Remove the accelerator pump discharge plug.
10.
Install accelerator pump discharge spring, P/N 17083343.
11.
Reinstall the accelerator pump discharge plug.
12.
Remove the existing accelerator pump and install P/N 17083344 accelerator pump.
13.
Reinstall the float and needle. (Hook needle clip over the crossbar facing seat. Do not hook through holes in float lever).
14.
Reinstall the mixture control solenoid.
15.
Reinstall the solenoid adjusting screw and turn it to lightly bottom the solenoid, then back it out the number of turns recorded during
disassembly.
16.
Reinstall the float bowl insert, metering rods, pump assembly, air horn gasket, and solenoid plunger.
17.
Reinstall the air horn.
18.
Reinstall the solenoid adjusting screw plug.
19.
Reinstall the air cleaner.
