Aeromotive 14127 - 99-04 5.4L LIGHTNING_HARLEY FUEL RAIL SYSTEM - Manual (Page 2)

The following steps are typical of most installations:
1. Once the engine has been allowed to cool, disconnect the negative battery cable and relieve fuel
system pressure, referring to the appropriate vehicle service manual for the procedure on doing so.
2. Remove the air intake ducting from the throttle body and position it out of the way.
3. Note the location of and remove any vacuum lines connected to the upper intake manifold and
position them out of the way.
4. Check for any dirt or debris around the fuel injectors. If any is evident, wash it off with some solvent
parts cleaner or wipe it off with a clean shop towel.
5. Disconnect the electrical connector at each injector, making note of the location of each.
6. Carefully relieve fuel system pressure per factory service manual.
7. Disconnect both the supply and return fuel lines from the OEM fuel rails. These lines are attached by
a special quick disconnect fitting which requires a special tool for removal. Place clean shop towels
around the open fuel lines to catch any gasoline that may drip out and to prevent any dirt from
entering the fuel lines.
8. Remove the vacuum line from the fuel pressure regulator.
9. Remove the bolts that attach the fuel rail to the lower intake (Typically there are 4 of them).
10. Place clean shop towels around the injectors to catch any gasoline that may be spilled during their
removal. Remove the injectors from the manifold by gently pulling upward on the fuel rail / injector
assembly. Keep all injectors connected to the fuel rails. If an injector does pull out of the fuel rail, it
may spill a large amount of fuel.
11. Carefully remove the fuel injectors from the OEM fuel rail.
12. Remove the old o-rings from the fuel injectors, inspect the injectors for any dirt or debris and clean if
needed. It is suggested that the old o-rings be replaced, contact your local Ford parts dept.
13. Coat the new fuel injector o-rings with a light oil to ease installation.
14. Carefully install the new fuel injector o-rings on the injectors.
15. Place a thin coat of light oil in the fuel rail fuel injector bores and in the lower intake manifold injector
bores to help prevent cutting the o-rings during installation.
16. Carefully place the fuel injectors in the fuel rails (depending on vehicle, placing the injectors in the
intake first might ease installation). Position the electrical connector on each fuel injector to the
opposite side of the fuel rail as the mounting bracket.
17. Install the driver side fuel rail, being careful not to cut any of the o-rings during Installation. The driver
side fuel rail will have a wider bracket spacing than the passenger side.
18. Install the passenger side fuel rail, being careful not to cut any of the o-rings during installation.
19. Find suitable place in the vehicle’s engine compartment to mount the Aeromotive regulator, typically
on the driver side wiring harness cover. This is located above the driver side fuel rail. Using the