Dohc mpfi swap finally
 

So i got a complete dohc zc. intake, exhaust, tranny, stage two clutch, motor, all the mounts, starter, alternator, wiring harness, all for 150. i put it in my dads hatch first (89 dx) to make sure that i can do the mpfi swap right. i didn't want to learn how to do it on my car (91 dx). it only runs on two cylinders.... #1 and 2. if you pull the injector plugs off and move them to another injector, it will run that cylinder. i have completely rechecked my harness, everything looks good. the ecu side is a little burnt (heat gun for saudering isn't a good idea) but its still making a good connection. i know in the swap, #1 and 3 are the stock fuel injector wires, and #2 and 4 are the wires you have to run to the injectors from the ecu. it does n't make sense that only #1 and 2 are firing becuase they are a mix of the two. i have also had someone tell me it could be the injector resistor box im using. im using the integra one, kinda looks like a metal twinky.
any help would be great, so post up.

Re: Dohc mpfi swap finally
 

Ok someone help me already.
i swapped out the injector resistor box and it still runs on two cylinders. i checked the completer engine harness. tore it all the way apart and put it back together. nothing wrong there. i swapped out ecu's, and when i swapped the pm5 (dx) it ran good for about ten seconds and died. i started it again and tried to rev it up but it died. i know that was cuz i switched the tps wires around, so i switched them back to the original way, and it still ran like ----. someone please help me out.

Re: Dohc mpfi swap finally
 

well obviously something with the wiring is screwed if only 2 injectors fire, any cels?

Re: Dohc mpfi swap finally
 

uh 1 and 16. o2 and fuel injector. i don't know what the ---- it is though. i know the o2 cuz its not even hooked up. open downpipe. but the fuel injectors are all getting power. took a multimeter and tested them, all have power.

Re: Dohc mpfi swap finally
 

what ecu are you using? a pm6,pm5, or pm7?

Re: Dohc mpfi swap finally
 

well i originally had the pm5, after the mpfi swap i put in the pm6. but just ------- around i put the pm7 in and it ran even worse. i put the pm5 back in and switched the tps wires back to there stock locations and it ran ok for about ten seconds. but it wouldn't start at all after that. so i switched the tps back and put the pm6 back in and now it still runs on 2 cylinders. it will rev up though.......

Re: Dohc mpfi swap finally
 

It sounds like something to do with the wiring. The pm7 should run the motor much better than the pm6. Are you sure you have the injectors wired in the correct sequence? If they aren't in the correct order it would def. seem like 2 aren't hooked up at all. Check this site out for the wiring swap...one of the best one's i've found and alot of help... http://gutterslide.com/fourthgenhatch_mirror/mpfi.html If all else fails, do a resistance check on the resistor box just in case. Also make sure you have all the injectors properly grounded too. I believe yel/blk wire ends up being the ground for the injectors and resistor box.

Re: Dohc mpfi swap finally
 

lol im the original poster of that write up, i found it on fourth gen hatch. i followed it to a t. i even tried both injector resistor boxes. i know its not the injectors becuase if i switch one of the injector wires to a different injector, it will run that cylinder. so its not that, but the only other thing i could think of is i kinda melted some of the wires on the plug "b" at the ecu. none are showing wires, but still. and i couldn't get one of the wires out of the plug, so i just cut it and soldered on a different wire with a little clip deal on the end of it from a different plug. i think thats the problem becuase when i pulled that wire out, it didn't change the way the car runs at all. so im going to head over to the junkyard on the way home from work and cut the plug off that i need. they have my parts car in there, and i know that has the plug i need.