Ford Thunderbird Manual page 253

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DESCRIPTION AND OPERATION (Continued)
Fuel Pressure Relief Valve
The fuel pressure relief valve (9H32 1):
is used to relieve fuel pressure from the fuel delivery
•
system.
is located on the fuel injection supply manifold
•
(9F792).
For fuel system pressure relief procedures, refer to
Section 1 0-0 1 .
Fuel Charging Wiring
The fuel charging wiring (90930):
connects the engine control sensor wiring ( 1 2A58 1 )
•
to each fuel injector and other electronic engine
controls such as throttle position sensor (TP
sensorX9B989) and idle air control valve (lAC
valve)(9F7 15).
receives fuel injector signals from the powertrain
•
control module (PCMX 1 2A650) and transfers the
signals to the fuel injectors.
The signals from the powertrain control module
determine the fuel injection sequence and duration
each fuel injector will stay open to allow fuel into the
combustion chambers.
Inertia Fuel Shutoff (IFS) Switch
The inertia fuel shutoff switch (IFS switch)(934 1 ):
• is used in conjunction with an electric fuel pump
(9350).
shuts off the fuel pump in the event of a collision.
•
consists of a steel ball held in place by a magnet.
•
When a sharp impact occurs:
the ball breaks loose from the magnet, rolls up a
•
ramp and strikes a target plate that opens the
electrical contacts of the inertia fuel shutoff switch
and shuts the fuel pump off.
• once opened, the inertia fuel shutoff switch must be
manually reset before restarting the vehicle.
Fuel Charging and Controls-4.6L (2V)
Fuel Pump Relay
The fuel pump relay ( 1 4N089) supplies power to the
fuel pump (9350) when the powertrain control module
(PCMX 1 2A650) grounds the relay during START and
engine RUN conditions.
A/ C Clutch Control Relay
The A / C clutch control relay ( 1 90572) is used to
improve idle smoothness after engine start-up and to
improve acceleration performance. The A I C is cut off
for approximately five seconds:
•
•
just after the engine is started.
when the throttle position sensor (TP
sensorX9B989) indicates a wide-open-throttle
(WOT) condition.
1997 Thunderbird, Cougar July 1 996
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A20827·A