Ford F150 Pickup. Manual — part 1155

Fig. 15: Identifying Lock-Down Valve Jackscrew
Courtesy of FORD MOTOR CO.

Engine Runs

2. Disconnect the Fuel Rail Pressure (FRP) sensor electrical connector.

3. Start the engine and allow it to idle until it stalls. Once the engine stalls, crank the engine for an

additional 15 seconds.

NOTE:

Running the engine with the FRP sensor electrical connector
disconnected will generate a DTC that will have to be cleared.

WARNING:

This step in the procedure will vent a very slight amount of residual
pressure to the atmosphere. Use care to prevent the combustion of
escaping fuel. Smoking, open flames or any kind of arcing must be
avoided. Carry out this operation only in a well-ventilated area.
Failure to follow these manuals may result in personal injury.

2003 Ford Pickup F150

2003 GENERAL INFORMATION Fuel System - General Information - Natural Gas - F150 Pickup

4. Slightly loosen the FRP sensor to release the residual pressure from the fuel rail.

5. Tighten and reconnect the FRP sensor.

6. Using the scan tool, access the FRP PID. The FRP PID should indicate less than 5 psi. If so, the fuel

system may be opened and serviced. If not, repeat the procedure.

Engine Does Not Run

Fig. 16: Locating Low Pressure Line Fitting
Courtesy of FORD MOTOR CO.

NOTE:

If the vehicle is being serviced for an FRP sensor DTC, the FRP PID
reading may not indicate actual pressure in the fuel rail.

WARNING:

This step in the procedure will vent pressure to the atmosphere. Use
care to prevent the combustion of escaping fuel. Smoking, open
flames or any kind of arcing must be avoided. Carry out this
operation only in a well-ventilated area. Failure to follow these
manuals may result in personal injury.

2003 Ford Pickup F150

2003 GENERAL INFORMATION Fuel System - General Information - Natural Gas - F150 Pickup

7. Slightly loosen the low pressure fuel line fitting until the fuel starts to escape. After the fuel is evacuated,

disconnect the fitting, install new O-rings, lubricate the O-rings with engine oil, and connect the fitting.

FUEL TANK EVACUATION

Special Tool(s)

2003 Ford Pickup F150

2003 GENERAL INFORMATION Fuel System - General Information - Natural Gas - F150 Pickup

Fig. 17: Identifying Special Tool(s)
Courtesy of FORD MOTOR CO.

WARNING:

The fuel supply lines will remain pressurized after engine shutdown.

2003 Ford Pickup F150

2003 GENERAL INFORMATION Fuel System - General Information - Natural Gas - F150 Pickup