How to Install Aeromotive FPR on RB25DET

The Aeromotive 13109 is an aftermarket replacement fuel-pressure regulator for the Nissan RB25DET engine. Nissan's RB series are 2.0 liter to 3.0 liter, twin cam, 6-cylinder engines installed in a number of Nissan models such as the Skyline between 1980 and 2004. The Aeromotive fuel-pressure regulator mounts between the fuel-injection rail and the injectors in the RB25DET electronic fuel-injection system and permits more precision adjustment of fuel pressure than the stock regulator for street or competition performance. Pressure adjustment in the 13109 ranges from 40 p.s.i. to 75 p.s.i.

Instructions

1

Disconnect the negative battery cable.

2

Follow the manufacturer's directions for your vehicle to relieve the fuel-system pressure.

3

Remove the vacuum line (if installed) from the OEM regulator.

4

Surround the OEM regulator with shop rags to soak up gasoline that may be spilled.

5

Remove the OEM regulator from its mounting hardware and disconnect the fuel lines from the input and output side of the regulator. Remove the OEM regulator from the vehicle.

6

Locate an appropriate place in the engine compartment for mounting the Aeromotive 13109 fuel-pressure regulator. Position the mounting bracket and mark the location of the two mounting holes.

7

Drill two holes at the marked spots with a No. 20 drill bit.

8

Attach the regulator to the bracket and mount the bracket in place with the two supplied No. 10 screws.

9

Connect the two fuel lines from the fuel rail outlet to the inlet ports on the side of the regulator. If a single fuel line is used for your vehicle, plug one of the fuel inlet ports on the side of the regulator with an AN-06 plug and O-ring.

10

Connect the fuel-return line to the outlet port on the bottom of the regulator.

11

Verify that all fuel-line connections are tight.

12

Coat the threads of a standard fuel-pressure gauge with thread sealant and install the fuel-pressure gauge into the one-eighth-inch NPT port on the front of the regulator.

13

Attach the vacuum hose (if installed) to the nipple on the right side of the regulator.

14

Remove all fuel-soaked shop rags and clean up any spilled gasoline.

15

Reconnect the negative terminal of the battery.

16

Turn the ignition to the "On" position but do not crank the engine. Allow a few seconds for fuel pressure to build, then check the reading on the fuel-pressure gauge. If there is no fuel pressure, turn the ignition to the "Off" position and repeat the procedure until the gauge shows fuel pressure.

17

Check the regulator and all connections for fuel leaks. If any leaks are noted, turn the ignition to the "Off" position before dealing with the leak.

18

Start the engine. Loosen the pressure adjustment screw locknut on top of the regulator and turn the adjustment screw to produce the desired fuel pressure. Clockwise turns of the adjustment screw increase the fuel pressure, and counterclockwise turns decrease the fuel pressure. Factory specifications for the Nissan RB25DET call for 43 p.s.i. fuel pressure. Tighten the pressure adjustment screw locknut on top of the regulator.

19

Test-drive the vehicle, evaluate performance and recheck the regulator and connections for leaks. Shut off the engine immediately if any leaks are noted.