27 November 2011

Fuel injector swap and AEM Fuel Rail Installation

I was running 280cc injectors off the Honda Prelude which are peak and hold (Low impedence) injectors.  Not required for my applications and I decided to swap them out to the DC2R injectors which are saturated (High impedence) injectors. First I had to remove the resistor box which has be used with the low impedence injectors so as to prevent the ECU from being fried (Low Impedence = Higher Current).

The resistor box are pointed out by the white arrow. Do note that the car does not comes with the resistor box installed originally.

In my case, I just need to join the red wire to the yellow/black wires.

Since I was working on the plugs, I decided to move them away from the original position to hide them away until I start my wire tuck project ;p

Left:  OBD1 Injector plug  Right:  OBD2 Injector plug

Next I had to swap out the the plugs, since the injectors are OBD2. 

Some heat shrink and high heat resistance conduit.

Just remember to match the yellow/black wires accordingly as on the plugs to the harness.

Next to remove the fuel rail.

Do remember to release the pressure in the fuel system by opening the fuel tank cap and pressure release bolt on the fuel filter.

Use a 19mm wrench and loosen the banjo/fuel damper. And remove the fuel regulator or in my case; a adapter. There are just 3 bolts holding the fuel rail in place.

Replace the rubbers seals/o-ring on the injectors.

The AEM fuel rail (Part no. 25-103BK) comes with everything that I needed to install it. Do change the injector seals instead of using back the old ones to prevent leaks.  The only problem I had was the AN6 nut on the right side, it was leaking quite badly although I installed the crush washer that came with it (The washer didnt fit very well, it was too big).  I had to use teflon tape to wrap around the nut to stop the leak.

Install the fuel regulator or adapter back

The banjo with the damper.

Check all bolts are tightened. Switch to ignition a few times to prime the fuel, check for leaks before starting engine.  Once engine started, check for leaks again and you are done.


  1. Anonymous7/6/13 15:33

    so can i take a obd1 wire harness and cut the clips off and wire on obd2 clips? will i have to run a resistor box? i am swapping a 97 b18c1 obd2 in a 94 civic ex obd1 having trouble with the injectors thanks bobby

  2. The resistor box depends on the type of injectors u will be using.
    Low Impedence: Need resistor box
    High Impedence: Remove resistor box