RuffRhyno

I converted my 91 DX to MPFI awhile ago but it has been giving me problems since. The B17a is running with very low power, and it stutters and bogs. There is nothing wrong with the motor, I just changed the headgasket too. Timing is perfect. So, I am led to the conclusion that something witht he fuel injectors is to blame...

I have gone over my wiring several times, and everything is fine. I rigged it up so that there are as little soldered connections as possible. I am thinking that it could be the actual power wire to the fuel injector resistor box that could be out of whack. What I wanted to know is if I can run a wire directly from the ECU to the injector resistor box. That way, there is not cutting and soldering involved in between.



In the pic above "A15" is the wire for fuel injector power. In every other instructional I have seen, the "A" plug is described as having 16 wires. So, This would actually be A13, considering the 2 blank pins that can't be used in the plug.

I have noticed that the fuel injector power wire has been cut and soldered (conversion error, don't ask) and that could possibly be causing the problem.

So in short, can I just run one wire from A13 to the injector resistor box (yellow/black wire)?

Bontke

I have wired up a few stand alone systems before and what i would suggest is to make sure the injectors are the correct resistence for your setup and check the fuel pump circuit. I wired one system that cut fuel pump voltage at a certain load and would increase it responding to engine load. Don't think that just the injector wiring is at fault, the computer controls more that just the injectors in the fuel system.

As long as you wire up the injectors like the diagram says you should be fine. Is the A15 wire a 12v constant source or does the computer manipulate it? It looks as if the A15 is a ground signal sent to the resistor box. What exactly is does I have no clue.

RuffRhyno

Modified by RuffRhyno at 12:52 AM 5/1/2003

yourfacesucks

dude i had the same problem....im almost 100% sure i know whats wrong its your number three injector its not getting any power....and i mean no power you need to rewire your number three injector to a larger power source.....not to the wiring harness but by itself i promise your car will run perfect after you do it.....this has happend twice with the same swap to us..........

RuffRhyno

I PM'ed you...

evilxkid

you can run any 12v power source to your resister box. your ecu dosn't manipulate it. even if the a plug is off by 2 pins there are two pins for power right next to each other, they are bolth yellow and black.

yourfacesucks

well when we put my b17a in my 91 hatch dx we ran into the problem of only the #3 injector not getting enough power we actually tapped the power off the injector and ran it straight to my battery and then the car ran perfect one of the guys who helped me with the swap said he had this problem before too....is your car lacking power like when you punch it it almost sounds like a putter and its not getting gas because thats the problem im talking about...try and tap the power wire off the #3 injector and run it straight to the battery and then rev up the car see if it sounds better....as of now when you rev your car it sounds real stuttery doesnt it well try that with the wire and then rev and see what it sounds like it should sound better.............its something about the wiring harness there are two powers for four injectors #2and #4 are on one and #1 and #3 are on the other and for some reason #2 and #4 injectors get enoughpower and so does #1 but not #3 try it and let me know what happens.......