If you own a CRX DX and plan to do anything performance related, this is in your future. Before we get into the actual converison, let me explain why this is important. The DX's came with a d15b2 equiped with a Dual Point Fuel Injection setup with a primary and a secondary injector. Not a bad setup for what it was designed for, but if you're on this message board you probably are going to be looking for a little more performance than Honda designed. With a Multi Point Fuel Injection conversion you get the luxery of after market support and upgradable injecters nevermind the benifits of having individual fuel injectors for each cylinder.
The easiest way to do this conversion is to modify your existing DX harness.
Parts needed:
-MPFI manifold
-MPFI Distributor
-Throttle body
-injectors (4)
-injector clips (4)
-resistor pack
-ECU (PM6 for a d15b2 conversion)
Wiring Inside car at ECU:
-
Depin C1 (orange) and C2 (white) and plug them into B10 and B12. Orange to B10, White to B12. Some cars have a wire in B12 even though it does nothing.
-Run wires from C1 and C2 into the engine bay. You can depin the wires from B2 and B11 and solder on some excess wire to achieve this or run new wire.
-Cut wires at A3 and A7 and leave some extra to connect to. Connect wire to it and run into engine bay.
*now you bolt the new manifold and throttle body and parts up*
Wiring on harness:
-Extend the TPS wires to reach the throttle body. On the TPS plug on the DX harness you will see 3 wires going to it, yellow, red, and green, in that order (if you are looking at the top of the clip from left to right on the DX clip). Depin and switch the green and yellow wires around so now the order is green, red, yellow.
-The EACV wires need to be extended also
-The DX has 2 injector plugs on it, cut them off as close to the plug as you can. Connect all the yellow/black wires from those injector plug wires and solder them all together. From that combined connection solder on another wire and run it to the yellow/black wire on the Injector Resistor Box.
-Connect the solid yellow wire from the DX injector to the #1 injector (I insert all the signal wires onto the left side of the injector plug, and all the resistor box wires on the right side, though I'm not sure it matters).
-Connect the solid red wire from the DX injector and run it to the #3 injector (onto the left side of the plug, like I mentioned above).
-Connect the A3 wire to the #2 injector (left side).
-Connect the A7 wire to the #4 injector (left side).
-Now run a wire from the right side of each injector plug and connect it to the red/black wires on the injector resistor box (the order doesn't matter from what I've seen).
Cylinder Position Sensor:
For DOHC engines such as the ZC
-Connect the C1 wire to the blue/green wire on the Cylinder Position Sensor (a sensor on the exhaust cam of the ZC).
-Connect the C2 wire to the blue/yellow wire on the CPS.
For SOHC engines such as the Si
-Connect the C1 wire to the blue/green wire on the CPS (the sensor is inside the Distributor on a SOHC engine). For doing this I suggest swapping out to the proper Si distributor plug so it is all plug and play and looks clean.
-Connect the C2 wire to the blue/yellow wire on the CPS.
That's it.
If you want a lot more info and pictures, check this link:
http://www.fourthgenhatch.com/mpfi.html
And here is another one that is a little more straight forward:
http://tech.hybridgarage.com/tech/4g...-zc-wiring.htm
Resistor pack wiring diagram:
Linear Mode
