AEM High Volume Fuel Rail 25104BK User Manual

							ADVANCED ENGINE MANAGEMENT INC. 
2205 126TH Street, Unit A Hawthorne, CA. 90250 
Phone: (310) 484-2322 Fax: (310) 484-0152 
Http://www.aempower.com 
Part Number: 10-282  
© Copyright 2001 
! WARNING 
 
 
 
 
 
 
 
 
 
 
HI-FLOW 
FUEL 
RAIL 
 
 
 
Installation Instructions for: 
Part Number 25-104 
1990-1993 Honda Accord 
1992-1996 Honda Prelude 
1997-2000 Honda Prelude 
 
 
 
Read and understand these instructions BEFORE attempting to install this product. 
  
						

							• Do not smoke while working on the fuel system. 
• Keep open flames or sparks away from your work area. 
• Be sure to relieve fuel pressure while engine is off. 
 
1) 
Getting started 
a)  Make sure vehicle is parked on a level surface. 
b)  Set parking brake. 
c) Disconnect the negative cable from the negative battery terminal. 
d)  If engine has run within the past two hours let it cool down.
 
e)  Clean the area around the fuel rail so that dirt cannot get into the engine. 
Note it is recommended to: 
•  Replace the washer between the service bolt and the special banjo bolt whenever the service bolt is 
loosened. (where equipped) 
•  Replace all washers whenever the bolts are removed. 
•  Replace all cushion rings, seal rings and fuel injector insulators when fuel rail is disassembled. 
2) Relieving fuel pressure 
a)  Remove the fuel fill cap. 
b) On models equipped with a 6mm service bolt. (illustrated below)  If your vehicle is not 
equipped with a 6mm service bolt, then proceed to step c. 
i)  Use a box end wrench on the 6mm service bolt on top of the fuel filter or fuel rail, while holding the 
special banjo bolt with another wrench.
 
ii)  Place a rag or shop towel over the 6mm service bolt. 
iii)  Slowly loosen the 6mm service bolt one complete turn. 
iv)  Leave service bolt loose until all pressure has been relieved. 
v)  Tighten service bolt to 10 lbf-ft. 
c) 
On models not equipped with a 6mm service bolt. 
i)  Use a box end wrench on the 12mm banjo bolt on top of the fuel filter. 
ii)  Place a rag or shop towel over the 12mm banjo bolt. 
iii)  Slowly loosen the 12mm banjo bolt one complete turn or until all pressure has been relieved. 
iv)  Torque the 12 mm banjo bolt to 25 lbf-ft. 
 
 
 
3) Stock fuel rail, injectors and fuel pressure regulator removal 
 Refer to following vehicle-specific diagrams for proper disassembly. 
a)  Disconnect the fuel inlet fitting at the fuel rail. 
i)  Be careful not to lose either of the two crush washers. 
b)  Disconnect the wire connectors from the fuel injectors.
 
Service Bolt 
 10 lbf 
z ft 
Fuel Filter Shop Towel  
						

							c)  Disconnect the vacuum hose from the fuel pressure regulator. 
d)  Place a rag or shop towel over the fuel pressure regulator. 
i)  Remove the two 6mm retaining bolts. 
ii)  Position the fuel pressure regulator out of the way. 
(1)  Be careful not to loose the o-ring that goes between the fuel rail and the fuel pressure regulator. 
e)  Loosen and remove the retainer nuts/bolts on the fuel rail, injector harness, and any other components 
that may be bolted to the fuel rail.
 
f)  Disconnect the fuel rail. 
g)  Remove the fuel injectors from the intake manifold. 
i)  Some models have an injector insulator on the injector tip (the end of the injector that goes into the 
intake manifold) and some models do not.  Note the arrangement your model has and be sure to 
reassemble the injector assembly correctly. 
h)  Inspect all seals, o-rings, and washers.  If any of these components look at all worn or damaged, then 
replace with genuine Honda parts. 
 
Fig. 1a: 90-93 Accord 
 
 
 
 
 
 
 
 
 
 
 
 
 
Fig. 1b: 92-96 Prelude 
  
						

							 
 
 
Fig. 1c: 97-00 Prelude 
 
 
  
						

							4) Assembly of the AEM Fuel Rail 
Refer to the attached vehicle-specific assembly drawings for proper assembly. 
a)  Line up the stock fuel rail with the AEM Fuel Rail. 
i)  Lubricate the threads of the fuel inlet fitting with a light coat of engine oil.  Install the fuel inlet fitting 
into the end, or the top, of the AEM Fuel Rail that matches the placement of the fitting in the stock 
fuel rail.  Make sure that one of the –6 crush washers is installed under the head of the fuel inlet 
fitting.  Be sure that the crush washer is centered under the head of the fuel inlet fitting. 
a) The AEM Fuel Rail comes with an additional fuel port. If you are running a wet nitrous oxide system, or 
a fuel pressure gauge, then this port may be used for the additional fuel supply.  If you are not in the 
need of an additional fuel source install the supplied 1/8” NPT plug. (Fig. 5)   
Note: When installing the tapered plug or any other tapered fitting into the AEM Fuel Rail, use only a 
lubricant or anti-seize on the threads.  Do not under any circumstances use liquid Teflon or 
Teflon tape as a sealant for any tapered plug or tapered fitting in any fuel system.
 
b)  Remove the old o-rings that are on top of the injectors. 
i)  Coat the new o-rings supplied with the kit, with clean engine oil. 
ii)  Install the new o-rings onto the injectors. 
c)  Insert the o-ring ends of the injectors into the AEM Fuel Rail. 
Note: To prevent damage to the o-rings, install the fuel injectors in the fuel rail first, then install them 
in the intake manifold.  
d)  Coat the seal rings with clean engine oil and then install them into the intake manifold. 
e)  Install the fuel rail/injector assembly back onto the vehicle. 
i)  Be careful to insure that none of the seals get damaged. 
ii)  Make sure that all seals and o-rings are properly seated. 
f)  Install and tighten the fuel rail retainer nuts/bolts. 
g)  Install the fuel pressure regulator onto the AEM Fuel Rail using the supplied bolts and washers.  Make 
sure that the o-ring is properly installed between the regulator and the fuel rail
. (Fig. 2)  Note:  If you 
are running the stock Honda fuel pressure regulator, DO NOT
 install the 
additional 1/8” NPT plug into the fuel return hole. On all applications, the fuel 
return hole will be located between the two threaded regulator mounting holes 
h)  Connect the vacuum hose to the top of the fuel pressure regulator. 
i)  Some kits require the replacement of this hose with a longer one.  If your kit requires this then 
replace the original vacuum hose with the one that is supplied in the kit. 
i)  Install the injector wire harness and related brackets, if equipped. 
j)  Install the fuel supply line to the AEM Fuel Rail. 
i)  Be sure that a crush washer is positioned on both sides of the banjo fitting. 
ii)  Torque the retaining nut to 12 lbf.-ft.  D
O NOT OVER TIGHTEN.  
iii) Make sure the plugs on the ends of the fuel rail are tight. 
k)  Install any remaining components that were removed during disassembly. 
5) Finishing Touches 
a)  Connect the negative battery terminal. 
b)  Turn the ignition switch to the on position for approximately two seconds.  Do not operate the starter.  
Then turn the ignition switch to the off position. 
c)  Repeat this procedure three times, and then check all components that were removed during installation 
for any signs of fuel leakage. 
i) Be sure to check the area around the fuel inlet fitting, the –6 plugs and the 1/8” NPT plug.  If 
these three items were not installed correctly then they may be prone to leak. 
d)  If there are signs of leakage you MUST
 correct the leak before proceeding. 
e)  If there are no signs of leakage, then start engine and again check for leaks. If there is any sign of 
leaking you MUST
 repair the leak before driving the vehicle. 
 
 
 
For Technical Inquiries 
Please E-Mail us at 
[email protected]