2003 FORD E SERIES fuel pressure

COMPRESSED NATURAL GAS (CNG) FUEL SYSTEM
Your vehicle is equipped with a dedicated compressed natural gas (CNG)
fuel system that is under high pressure.
Depending upon the application, the CNG fuel system is rated at a
pressure of 20,700 kPa (3,000 psi) at 21°C (70°F) or 24,800 kPa (3,600
psi)at21°C (70°F). Refer to the label on the fuel filler door to
determine the fuel system pressure rating.
Use caution when servicing or maintaining any of the components of the
CNG fuel system.
Service to high-pressure fuel system components must be
conducted only at qualified dealerships by qualified technicians.
Failure to do so may cause damage to components or cause bodily
harm.
On F-Series natural gas vehicles,do not modify or replace the bed
with any non-OEM components. Should the bed need to be removed for
service or replacement, it should be done by a qualified dealership using
qualified technicians. Do not sit, stand or place heavy loads on in-bed
tank cover. Any bed cap added to this vehicle must be well ventilated.
Failure to provide adequate ventilation could result in gas vapor build up
over time potentially resulting in a combustible mixture.
Introduction
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FUEL GAUGE
The fuel gauge in your NGV behaves similarly to a typical gasoline fuel
gauge. However, the gauge operation is based on the pressure and
temperature of the natural gas, not on the level of liquid gasoline.
Depending upon application, a fuel gauge reading of Full will occur at a
pressure of approximately 20,700 kPa (3,000 psi) or 24,800 kPa (3,600
psi), at a temperature of approximately 21°C (70°F). The NGV fuel
gauge will provide a linear reading from this point down to Empty. Refer
to theFuelingsection of this supplement for more information on fuel
gauge performance during the fast-fill method of fueling.
Instrumentation
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E-450 Cutaway
1.Fuel rail sensors-An injection pressure sensor and an engine fuel
temperature sensor provide engine fuel information to the powertrain
control module.
2.Isolation solenoid valve-Blocks fuel flow from supply line to
injection manifold when the engine is off.
3.Engine-A modified 5.4L gasoline engine with Sequential Electronic
Fuel Injection (SEFI), an improved valvetrain and a high compression
ratio.
4.Powertrain control module-Uniquely calibrated for NGV application.
5.Extended range fuel tank-An optional steel fuel tank located in the
cargo area.
6.Sealed vent box-Dispenses natural gas vapor to atmosphere if vapor
becomes present.
7.Internal tank valve-One electronically actuated, normally closed
solenoid valve is located in each fuel tank. The valve is wired into the
vehicle’s inertia switch. If the engine cranks but does not start after a
collision, the fuel solenoid valve inertia switch may have been activated.
The inertia switch is a device intended to close the fuel solenoid valve
when your vehicle has been involved in a substantial jolt.
8.Stone shield(s)-Protective shield(s) to prevent damage to the fuel
tank(s) caused by road debris or other road hazards.
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Servicing your vehicle
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9.Aft axle fuel tanks-Two steel fuel tanks located behind the rear axle.
10.Midship fuel tank-A steel fuel tank located underbody.
11.High pressure fuel lines-Delivers high pressure fuel to the fuel
tanks and fuel pressure regulator.
12.Fuel pressure regulator/Coalescent fuel filter-Reduces fuel
pressure to 95 psi and removes impurities from the gas.
13.Low pressure fuel line-Supplies 95 psi of natural gas to the
injectors.
14.NGV module-Contains the unique powertrain electronics that are
required for an NGV.
F-Series Pick-up
1.Fuel rail sensors-An injection pressure sensor and an engine fuel
temperature sensor provide engine fuel information to the powertrain
control module.
2.Isolation solenoid valve-Blocks flow from supply line to injection
manifold when the engine is off.
3.Engine-A modified 5.4L gasoline engine with Sequential Electronic
Fuel Injection (SEFI), an improved valvetrain and a high compression
ratio.
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Servicing your vehicle
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4.Powertrain control module-Uniquely calibrated for NGV application.
5.Internal tank valve-One electronically actuated, normally closed
solenoid valve is located in each fuel tank. The valve is wired into the
vehicle’s inertia switch. If the engine cranks but does not start after a
collision, the fuel solenoid valve inertia switch may have been activated.
The inertia switch is a device intended to close the fuel solenoid valve
when your vehicle has been involved in a substantial jolt.
6.Standard fuel tanks-Two steel fuel tanks located in the bed of the
truck.
6b.In-bed tank cover-Cover to prevent damage to the fuel tanks.
Protective shield to prevent damage to the fuel tank caused by road
debris or other road hazards.Do not sit, stand or place heavy loads
on the fuel tank cover.
7.Stone shield-Protective shield to prevent damage to the fuel tank
caused by road debris or other road hazards.
8.Underbody fuel tank-A steel fuel tank located underbody.
9.High pressure fuel lines-Delivers high pressure fuel to the fuel
tanks and fuel pressure regulator.
10.Fuel pressure regulator/Coalescent fuel filter-Reduces fuel
pressure to 95 psi and removes impurities from the gas.
11.Low pressure fuel line-Supplies 95 psi of natural gas to the
injectors.
12.NGV module-Contains the unique powertrain electronics that are
required for an NGV.
Servicing your vehicle
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Crown Victoria
1.NGV module-Provides power for the fuel injectors. Also, drives the
fuel gauge using fuel tank pressure and temperature sensors.
2.Isolation solenoid valve-Blocks flow from the injection manifold
when the engine is off.
3.Engine-Is a modified 4.6L engine with Sequential Electronic Fuel
Injection (SEFI) and increased compression ratio.
4.Engine coolant lines-Provide required heat to high pressure
regulator.
5.Powertrain control module-Required for NGV application.
6.Sealed vent box-Vented to underbody. Dispenses natural gas vapor
to atmosphere if vapor becomes present.
7.Tank pressure sensor-Fuel tank pressure sensor located in this
tank’s solenoid valve is used for fuel indication.
8.Solenoid tank valves-One solenoid per tank. Internal valves with
shut-off solenoids wired into inertia circuit for crash protection.
9.Two fuel tanks-Located in the trunk. On taxi or police vehicles, an
extended range fuel system is available which includes two additional NG
fuel tanks mounted in the trunk (total of three).
10.Fueling point-Fueling receptacle is conveniently located with the
fuel door. Same location as gasoline fueled vehicles.
11.Tank shield-Protective shield able to prevent damage to the fuel
tanks caused by trunk cargo.
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12.Tank temperature sensors-One each in set of tanks (solenoid
valves) used for fuel indication.
13.Optional fuel tank-A fiber-wrapped steel fuel tank (total of three
tanks in the trunk). Also has a sealed vent box which vents to the
underbody. Dispenses natural gas vapor to the atmosphere if vapor is
present.
14.Two fuel tanks-Located underbody to facilitate fuel system design.
15.Stone and heat shield-Protective shield able to prevent damage to
the fuel tanks caused by road debris or other road hazards.
16.High pressure fuel lines-Delivers high pressure fuel to the pressure
regulator.
17.Pressure regulator and coalescent fuel filter assembly-Reduces
the fuel pressure to the fuel injection pressure of 125 psi.
18.Low pressure fuel lines-Supplies 125 psi of natural gas to the
engine.
19.Fuel rail sensors-One injection pressure sensor and one engine fuel
temperature sensor provide engine fuel information to the PCM.
ADAPTERS
DO NOTuse fuel receptacle adapters when refueling your vehicle.
The profiles of both the natural gas vehicle receptacle and the fuel
station nozzles are specified by ANSI/AGA NGV1-1994, CGA NGV1-M94.
These profiles are specified for compressed natural gas vehicles and fuel
stations for safety purposes. Three separate adapter profiles are
available. P24, P30 and P36 respectively, are specified for the three
different service pressures of 16,500 kPa (2,400 psi), 20,700 kPa (3,000
psi) and 24,800 kPa (3,600 psi).
Your vehicle’s service pressure may be 20,700 kPa (3,000 psi) or 24,800
kPa (3,600 psi), depending upon application. Refer to the label on the
fuel filler door:
•If your vehicle’s fuel system is rated at 20,700 kPa (3,000 psi), it can
be refueled using a P30 or P24 nozzle. However, use of a P24 nozzle
will result in an incomplete fill.
•If your vehicle’s fuel system is rated at 24,800 kPa (3,600 psi), it is
refueled using a P36 nozzle only.
DO NOT over pressurize the CNG fuel system or damage to the
fuel system and possible personal injury may occur.
Servicing your vehicle
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NATURAL GAS DISPENSING
Most dispensers have a digital indicator displaying the cost and amount
of fuel delivered to your vehicle. Fuel delivery to the vehicle is stopped
when the pressure of fuel stored on the vehicle equalizes with the
temperature compensated pressure of fuel stored at the station. As the
pressure between the station and vehicle equalizes, the cost and quantity
meters slow to a near stop. When this occurs, refueling is complete.
Certain noises can be expected during the refueling process and may
vary depending on the type of fuel station and your proximity to the fuel
compression and storage equipment. At the beginning of refueling you
might hear the rushing noise of gas entering the vehicle through the
station hose and tubing. At the end of refueling, the fuel receptacle on
the vehicle may make a high pitch noise or chatter. This is another
indication that refueling is nearly complete. Also, the station compression
equipment may turn on at any time during the refueling process.
FUEL QUALITY
Use only a CNG fuel that meets the specification of NFPA-52 and SAE
J1616 in your NGV. Specifications NFPA-52 and SAE J1616 place limits
on particulate contamination and moisture content to ensure a quality
CNG fuel.
The use of a CNG fuel that does not meet specifications NFPA-52 and
SAE J1616 isnot recommendedand may cause engine damage.
Use of poor quality CNG fuel may result in:
•component failure.
•leakage from the fueling point.
•poor vehicle operation.
Use of poor quality fuel may also result in your warranty being
invalidated.
SERVICING YOUR NATURAL GAS VEHICLE
Service to the CNG fuel system should be conducted at a
qualified dealership by a trained NGV technician only. Failure to
do so may cause damage to components or cause bodily harm.
Servicing your vehicle
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