AEM 25-392 Honda/Acura Adjustable Fuel Pressure Regualtor - Manual (Page 3)

WARNING!!!
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 on the fuel rail adjacent to the regulator.
f) Relieve fuel pressure. Refer to factory service manual for proper procedure.
2) Fuel pressure regulator removal
a) Place a rag or shop towel under the fuel pressure regulator return line.
b) Disconnect the fuel return line at the bottom of the fuel pressure regulator.
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 if regulator is mounted to a factory fuel rail.
(1) If using an AEM universal fuel pressure regulator, remove fuel inlet hose.
ii) Remove the fuel pressure regulator from the vehicle.
3) Changing the diaphragm/orifice
a) Remove the six bolts from the top of the fuel pressure regulator.
i) When removing t he six bolts from the top of the fuel pressure regulator a 9/64” allen key should be
used.
(1) Torque to 24 lbf-in.
(2) There is a constant pressure applied to the diaphragm by the spring inside the fuel regulator. Make
sure parts do not get lost upon removal of these bolts.
ii) When removing the orifice a 3/8” socket should to be used.
(1) Note: Be careful not to scratch or damage the surface of the orifice in any way, as it is a
precision ground surface for the diaphragm to seal on.
(2) Torque to 10 lbf-ft.
(3) There are three different size orifices supplied in the AEM fuel pressure regulator kit, which are
indicated by three different colors. Black = .100” Silver =.150” Gold = .200”
(4) Upon re-installation of the orifice use a light coat of oil on the threads to prevent galling.
iii) Re-assemble the fuel pressure regulator. Assembly diagram at the end of the instructions. Make sure
the diaphragm is properly seated in its groove. Use care to avoid pinching the diaphragm between the
top and bottom regulator housing.
4) Finishing touches
a) Reinstall the regulator by reversing the removal procedures from step 2.
b) Connect the negative battery terminal.
c) 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.
d) Repeat this procedure three times, and then check all components that were removed during installation for
any signs of fuel leakage.
e) If there are signs of leakage you MUST correct the leak before proceeding.
f) 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.
g) Note: To check the fuel pressure, start the engine. Measure the fuel pressure with the engine idling
and vacuum hose of the fuel pressure regulator disconnected from the fuel pressure regulator and
pinched.