Pontiac Fiero 1988 Service Manual page 380

FUEL SYSTEM 6C-9
15. Put six gallons of clean fuel into fuel tank and
apply 12 volts to Terminal "G" of ALCL to
operate fuel pump. Pump two quarts of fuel into
fuel can. This will purge fuel pump.
16. Remove hose and connect fuel hose to chassis
pipe.
17. Check all connections for leaks; tighten all hose
clamps.
FUEL TANKLLAK TEST PROCEDURE
1. Plug all outlets as follows:
a. Install plug at filler neck and vent hoses.
b. Install fuel meter with new gasket and plug
fuel line.
c. Install short piece of fuel line hose on fuel
meter vent tube.
2. Apply air pressure to tank through vent tube. Use
extreme caution to prevent rupturing the tank.
When air can be heard escaping from filler neck
cap (approximately 7 to 10 kPa or 1 to 1-1/2 lbs.
of pressure) pinch the fuel line hose to retain
pressure.
3. Test repaired area for leaks with soap solution, or
by submersion. If leak is noted, make repair and
retest.
FUEL TANK REPLACEMENT
1. Remove all fuel, see Draining Fuel Tank.
2. Support fuel tank and disconnect the two fuel
tank retaining straps.
3. Lower tank enough to disconnect sending unit
wire, hoses, and ground strap, if so equipped.
4. Remove tank from vehicle.
5. Remove sending unit. See Fuel Gage Sending
Unit Replacement.
FUEL TANK
Removal
1. Relieve fuel system pressure, (see Fuel System
Pressure Relief).
2. Disconnect negative battery cable.
3. Drain fuel tank (see Draining Fuel Tank).
4. Raise vehicle on hoist.
5. Disconnect fuel filler neck hose and vent hose.
6. Support fuel tank.
7. Remove fuel tank strap support bolts and lower
tank enough to disconnect fuel sending unit wire
and ground wire.
8. Disconnect fuel line, fuel vapor line and fuel
return line.
9. Remove tank.
Installation
Reverse removal procedure. Replace all sound
deadeners that were removed. Replace fuel and check
for leaks.
FUEL GAGE SENDING UNIT
Removal
1. Remove fuel tank, see Fuel Tank Removal.
2. Using Tool J-24187, or equivalent, remove
locking cam.
3. Remove sending unit and gasket, with fuel pump.
4. Remove strainer and clean by blowing out with
compressed air. Reinstall in correct orientation
on pump.
5. Remove fuel pump from sending unit by pulling
fuel pump assembly into rubber connector and
sliding pump away from bottom support. Care
should be taken to prevent damage to rubber
insulator and fuel strainer during removal. After
pump assembly is clear of bottom support, pull
pump assembly out of rubber connector for
removal.
Installation
Reverse removal procedure to install. When
installing locking cam, it may be necessary to compress
gasket slightly by pressing down on tool. Once cam
lock is started under retaining tangs, pressure may be
released.
FUEL, FUEL RETURN, AND EMISSION PIPE
REPAIR OR REPLACEMENT
1. If replacement of a fuel feed, fuel return or
emission pipe is required, use welded steel tubing
meeting GM Specification 124-M, or its
equivalent.
2. Do not use copper or aluminum tubing to replace
steel tubing. These materials do not have
satisfactory durability to withstand normal
vehicle vibrations.
3. When rubber hose is used to replace pipe, use
only reinforced fuel resistant hose which is
identified with the word "Fluroelastomer" on the
hose. Hose inside diameter must match pipe
outside diameter.
4. Do not use rubber hose within 100mm (4") of any
part of the exhaust system, or within 10 inches of
the catalytic converter.
5. In repairable areas, cut a piece of fuel hose
100mm (4 inches) longer than portion of the line
removed.
If more than a 6 inch length of pipe is removed,
use a combination of steel pipe and hose so that
hose lengths will not be more than 10 inches.
Follow the same routing as the original pipe.
6. Cut ends of pipe remaining on car square with a
tube cutter. Using the first step of a double flaring
tool, form a bead on the end of both pipe sections.
If pipe is too corroded to withstand bead
operation without damage, the pipe should be
replaced. If a new section of pipe is used, form a
bead on both ends of it also.
7. Use screw type hose clamp No. 2494772, or
equivalent. Slide clamps onto pipe and push hose
51mm (2 inches) onto each portion of fuel pipe.
Tighten clamps on each side of repair.
8. Pipes must be properly secured to the frame to
prevent chafing.