Ford F150 Pickup. Instruction - part 1331

3. Ensure the filter element adapter is in place in the upper filter housing. See Fig. 22 . To install, reverse 

removal procedure. Tighten fuel fitting. See FUEL LINE FITTINGS . After installation is complete, 
fuel lines and fittings must be leak tested. Perform COMPRESSED NATURAL GAS LEAK TEST 
under FUEL SYSTEMS in SYSTEM & COMPONENT TESTING - CNG article.  

 

2003 Ford Pickup F150 

2003 ENGINE PERFORMANCE Removal & Installation - F150 Pickup - CNG

  

Fig. 21: Identifying Coalescer/Fuel Filter Components 
Courtesy of FORD MOTOR CO. 

 

2003 Ford Pickup F150 

2003 ENGINE PERFORMANCE Removal & Installation - F150 Pickup - CNG

  

Fig. 22: Locating Filter Element Adapter 
Courtesy of FORD MOTOR CO. 

FUEL PRESSURE REGULATOR 

Removal & Installation 

CAUTION: If CNG system is being disconnected for an extended period, cover all 

open hose fittings and electrical connections to avoid contamination.

WARNING:

DO NOT reuse copper washers in low-pressure fittings, always use NEW 
copper washers.

NOTE:

Coolant lines may be attached to either coolant fitting of fuel pressure 
regulator. There is no preferred coolant flow direction. Ensure all coolant hoses 
DO NOT come in contact with engine mount bolts or other components. When 
vehicle battery is disconnected and reconnected, some abnormal drive 
symptoms may occur until vehicle relearns adaptive strategy.

NOTE:

The fuel pressure regulator and coalescer/filter are removed as an assembly.

 

2003 Ford Pickup F150 

2003 ENGINE PERFORMANCE Removal & Installation - F150 Pickup - CNG

  

1. Release fuel system pressure. See FUEL SYSTEM PRESSURE RELEASE . Disconnect negative 

battery cable. Pinch off the coolant lines 3" from the fuel pressure regulator (1). See Fig. 23 . Disconnect 
the fuel pressure regulator coolant lines (2). Disconnect low pressure fuel line from fuel pressure 
regulator and high pressure fuel line from coalescer/filter. See Fig. 24 . Loosen fitting retaining fuel 
pressure regulator to coalescer/filter. See Fig. 25 . Remove bolts retaining fuel pressure regulator to 
mounting bracket. See Fig. 26 . Remove bolts retaining coalescer/filter to mounting bracket. See Fig. 20 . 
Remove fuel pressure regulator and coalescer/filter assembly from the vehicle. Separate the fuel pressure 
regulator from the coalescer/filter. 

2. To install, reverse removal procedure. After installation is complete, fuel lines and fittings must be leak 

tested. Perform COMPRESSED NATURAL GAS LEAK TEST under FUEL SYSTEMS in SYSTEM 
& COMPONENT TESTING - CNG article.  

Fig. 23: Removing Fuel Pressure Regulator Coolant Lines

NOTE:

On installation, use NEW "O" rings. Lubricate NEW "O" rings with 5W-30 motor 
oil.

NOTE:

Numbers in parenthesis refer to numbers in illustration.

NOTE:

Install new "O" rings, lubricated with SAE 5W-30 motor oil.

 

2003 Ford Pickup F150 

2003 ENGINE PERFORMANCE Removal & Installation - F150 Pickup - CNG