hey i got a new 91 civic DX all stock DPFI and i was gonna convert all my stuff from my old 90 civic si which has the obd1 conversion plugs and everything needed for that but is it possible to use all of it and have the ecu plugs repin to make it work with my MPFI harnes? im getting rid of 90 civic si shell; its junk.

 

Why does your 90 si have an OBD1 harness?

I highly suggest converting the existing DPFI harness in the 91 civic into a MPFI harness, rather than using and trying to re-pin the Si harness. It will save you a big headache.

 

second on that idea... it will make life easier on you if you go ahead and just convert the harness. Just check the faq section for a how to and you should be aok... and put as much of that si into that 91 as possible because if you don't you will regret it later.

 

its converted to OBD1. i got a P28 with obd1 injectors and etc. another thing i was gonna do is convert the whole harness under the dashboard so then everything would plug in with the si harness without modifying any harness. well i converted my buddies civic STD to an civic Si harnesss by getting him the complete harness under the dashboard that runs the headlights and etc. And the Si engine harness so that way he wouldn't have to convert the harness to MPFI. just switching the whole Si harness over seem cheaper and cleaner so im probably gonna do that instead.

 

just take the entire dash harness and engine harness from the obd1 car and put it in your dx.
bam what an easy answer huh

 

you mean the whole cabin harness right.....just wire your dpfi harness for mpfi unless you want to rip out your interior and dash

 

if you ONLY wanna convert to mpfi, keep the si harness, move pins c1 and c2 to b10 and b12. add 2 wires at a3 and a7 and run them to engine bay for the 2 extra injectors. THEN add 2 more wires BACK at c1 and c2 and run those to your dizzy(you need an d16a6 crx si dizzy to convert and a pm6 ecu) and connect them to the 2 white wires. you CAN use a resistor box if you wanna or you can just hard wire the injectors straight off the ecu like i did. you should have a total of 6 wires, 2 for the dizzy and 2 for the injectors and the 2 that you moved to b10 and b12

 

yup

 

im keepin it obd1 , i wouldnt go back to obd0

 

keeping what obd1? the motor or the wiring harness??

 

i got a 95 ZC vtec motor running a P28 ecu so its staying obd1. the engine harness is converted for OBD1 anyway. i have the ecu conversion plugs. i got everything for it. all i was wondering of doing is using the engine harness to run in my dx civic and convert the ecu harness to mpfi so i can use my engine harness. im starting a new project.