to the tank until the pressure is relieved. This is due
to the leak detection pump closing the vapor outlet
from the top of the tank and the one-way check valve
not allowing the tank to vent through the fill tube to
atmosphere. Therefore, when fuel is added, it will
back-up in the fill tube and shut off the dispensing
nozzle. The pressure can be eliminated in two ways:
1. Vehicle purge must be activated and for a long
enough period to eliminate the pressure. 2. Removing
the fuel cap and allowing enough time for the system
to vent thru the recirculation tube.
CONTROL VALVE
DESCRIPTION
It is a valve in the top of the fuel tank that con-
trols fuel fill rate and fuel fill level and directs
vapors to a storage area.
OPERATION
The valve controls the fuel fill rate and set the fuel
level in the fuel tank. It also allows the proper oper-
ation of OBDII leak detection monitor. It prevent liq-
uid fuel carry over into the EVAP system (Fig. 4).
QUICK-CONNECT FITTINGS
DESCRIPTION
Different types of quick-connect fittings are used to
attach various fuel system components. These are: a
single-tab type, a two-tab type or a plastic retainer
ring type. Some are equipped with safety latch clips.
Refer to the Service Procedures section for more
information.
CAUTION: The interior components (o-rings, spac-
ers) of quick-connect fitting are not serviced sepa-
rately. Do not attempt to repair damaged fittings or
fuel lines/tubes. If repair is necessary, replace the
complete fuel tube assembly.
Fuel tubes connect fuel system components with
plastic quick-connect fuel fittings. The fitting con-
tains non-serviceable O-ring seals (Fig. 5).
CAUTION: Quick-connect fittings are not serviced
separately. Do not attempt to repair damaged quick-
connect fittings or fuel tubes. Replace the complete
fuel tube/quick-connect fitting assembly.
OPERATION
The quick-connect fitting consists of the O-rings,
retainer and casing (Fig. 5). When the fuel tube
enters the fitting, the retainer locks the shoulder of
the nipple in place and the O-rings seal the tube.
ROLLOVER VALVES
DESCRIPTION
All vehicles have rollover valve(s) on top of the fuel
tank.
OPERATION
The valves prevent fuel flow through the fuel tank
vent valve hoses should the vehicle rollover.
The rollover valves on the fuel tank are not ser-
viceable.
FUEL TUBES/LINES/HOSES AND CLAMPS
DESCRIPTION
Also refer to Quick-Connect Fittings.
WARNING: THE FUEL SYSTEM IS UNDER A CON-
STANT PRESSURE (EVEN WITH THE ENGINE OFF).
BEFORE SERVICING ANY FUEL SYSTEM HOSES,
FITTINGS OR LINES, THE FUEL SYSTEM PRES-
SURE MUST BE RELEASED. REFER TO THE FUEL
SYSTEM PRESSURE RELEASE PROCEDURE IN
THIS GROUP.
Fig. 5 Typical Plastic Quick-Connect Fittings
1 – CASING
2 – WINDOW
3 – RETAINER TAB
4 – NIPPLE
5 – O RINGS
6 – WINDOW
7 – RETAINER “EAR”
JX
FUEL SYSTEM
14 - 5
DESCRIPTION AND OPERATION (Continued)