MPFI swap wirin questions...

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M

MSRJDub

New Member
Ok so heres the deal.Me and my younger brother are swaping a sohc zc into his 91ef and everything has been goin very well up untill now.I searched the forums for some help,really couldn't find anything that seemed helpful.So I just have 2 questions-(I'm useing the writeup stickyed(sp?)here by "racingtweek")

1)Where it tells you to run the 4 wires for the injectors,am I suposed to just cut the mat the ecu and run them from there and let the unused part running to the entire harness hanging there,or am I supposed to splice into the wires?

2)Isn't really a question,but I'm having a really hard time removing the ecu pins,and I really dont want to break any clips,so any advice would be greatly appreciated.


So thanks in advance for any help you guys.I would like to get this damn wiring done so my brother can get off my ass and we can get this damn car on the road.
 
my advice would be dont run the 4 wires for the injectors i tried that and its more difficult then just run one from A3 and one from A7 and use the injectors from the DX harness
and about the depining thingy its a bitch! lol just get a paper clip and smash the end till it gets flat its easier then using a nail in my opinion
good luck
 
efhondakid said:
hondaswap.com/.../dpfi-mpfi-writeup-49557/

The search button my friend, it took me <than 2 minutes to find this. BTW good luck with the swap I did mine I thought it was going to be hard as shit until I gathered up a little more info and really looked at it and it was pretty easy.
Click to expand...


Well first,I am very aware of the search button and that writeup,I mean,the damn things stickied/pinned or whatever you want to call it,and that was the whole purpose of this thread.That writeup does not clarify if I'm supposed to just cut,or splce into the 4 wires as I previously stated.Thanks for trying though.


And the whole thing about the pins is,I'm not sure if I'm supposed to just pry them out,or if theres an easier way to release them.


I do apreciate you guys trying though.
 
Ok I have a grasp on the whole swap thing. I just completed the swap myself. The best way to do the swap is to change the entire body harness out for one that was in a car that had MPFI. The write up your doing your car with wont tell you that once you get the wiring done your crank angle sensor inside the distributor may or may not work. You may or may not get a TDC code at the ECU after completion of the swap. Oh yea and if your car flashes a series of codes and your car wont start you have to swap the damn computer all togther. Granted thats not a big deal but the fact still stands. Anyway enough with the negative crap. Im only telling you this because this is what I had to go through with 3 different cars. As for the the de pinning at the ECU get a very small flat head screw driver ( one for repairing eye glasses) and use that to push down on the little lock inside the plastic housing of the wires then the wire simply pulls out with little or any force what so ever. Good luck take my advice and swap the whole harness it takes about 2 hours to remove from the car and its not the difficult to replace most EF minus the Si Rex with the push button dash all have similiar wiring.
 
I became a member of this forum because I couldnt do the dpfi to mpfi. But yes, cut the wires coming out of the pins long enough to solder the wires you added for thr swap and you should be good. In no way was I trying to be a dick, sorry if I came off that way.
 
efhondakid said:
I became a member of this forum because I couldnt do the dpfi to mpfi. But yes, cut the wires coming out of the pins long enough to solder the wires you added for thr swap and you should be good. In no way was I trying to be a dick, sorry if I came off that way.
Click to expand...

It's all good.You did kinda come off like a dick,but with all the stupid ass questions I see on here without people searching,I wouldn't blame you if it was intentional.But yeah,that answered my question perfectly.Appreciate it man:D

Re-Ronin:I would love to do it that way.The only problem is its my little bros car,and the only reason hes doing the swap is because its basicly costing him nothing.My homie gave him the motor for free.He's straped for cash since hes got a new truck payment,so I doubt he'd shell out the money for the whole mpfi harness.
And about the pins,do you mean just pry the pins open slightly and remove the wire?Ifd so good,I was under the impression the whole pin would have to come out.

So I guess I just gotta deal with the pins,everything else is really straight foward now.Appreciate it guys.Any continued support is greatly apreciated.
 
Not exactly the plastic housing has sorta of a lock in it that locks into the metal fitting on the wire all you need to do is gently pry the lock up then gently pull the wire and the metal fitting out of the platstic housing. just remember which one it came out of it you are just soldering the wires together. Good luck

TRU
 
Right on.Well I'm to the point to where I might be able to just avoid dippining anything and just cut and solder everything.

I have one more question though.It says B12 should be empty,but the clip on this car is occupied by another wire(red/white).I know I'm not looking at the clip wrong,so my question is does anyone know the function of this wire,and if I'm supposed to just disconnect it or not.

Thanks for the continued help guys.
 
Double check that you are looking at the plug the right way, and if it has a wire already in that spot, just cut it, leaving enough to strip and solder the wire you are adding on to it, then tape the original wire you cut out of the way.
 
Thas what I originally planned to do,but I just wanna make sure it's not a wire I'm gonna need to re-route or anything.
 
Nope cut it off, I did the dpfi to mpfi and vtec on my DX and had the same problem your telling me now, I cut them off put the new wires on and no CELs everything works fine, I was a little unsure at first too but just said fuck it and did it. Ive got like 4 wires that went to the ECU that I cut and just tucked back into the loom.
 
Just came back in from the garage.Almost done :).

I still need an extra ecu pin so I can input C1 to B10,and then just run the 2 wires from A3&7 to the injectors.Then hopefully we don't throw any codes and we can start this son bitch.

Thanks for all the help you guys,I'll let you know how it goes.
 
Ah now that you say that you do have to depin one because you have to run a wire to a spot that doesnt have anything in it.
 
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Hey guys.I got another question(fuck)

So I finished up all the wiring about an hour ago and we preceded to get it ready to start.We put the batery back in,plugged the ecu in and whatever else needed to be done.Now there are 2 seperate problems we have.

1)When we turn the car to"on",the normal lights in the cluster come on,but there flashing from brite to dim,and were get a wierd constant sdoun from what I beleave is the relay switch(not sure on the name,the little black box on the driver side footwell)and we're not sure what the reason is for that.

2)even though the cluster was goin nutts,we decided to give it a go and try to start it,the car was atempting to start,but on the valve cover righ tnext to one of the valve cover washers,we keep getting this little spark everytime we try to turn it over,but the car is trying to turn over even after that.

I know some of this is vague,and I won't be able to provide any pics/vid/or sound untill tomarow night when I get my camera back from my girlfriend.So once again,your help is greatly apreciated guys and I hope to hear from ya.Thanks.
 
1. That black box in the drivers footwell is the main relay.
2. Check all your grounds and go over your wiring to make sure its 100%

It sounds to me like a bad ground somewhere though. GL.:thumbsup:
 
K,thought that was what it was called.My brother continued to mess with it.It does have something to do with the main relay,because when he disconects it and turns the power on,the car doesnt make a noise and the cluster lights are fine.
Also,from just being on,or from trying to start the car,the ground wire attached to the valve coverand frame section next to the driver side headlight,heated up to the point there was a small bit of smoke rising up from it.

I'm gonna wait till tomarow to work on it anymore,so we'll see how it goes,if I can'
t find out,then I'm gonna take some pics and vid and see if you guys can help me out.Appreciate guys(mostly "Byron",ha).
 
Thanks, just telling you what I know from my experiences with my DP to MP swap. I dont know why your engine ground would be getting hot like that. Did you do a battery re-location to the back of the car? And you can pull the main relay apart, and see if the solder inside is all melted.
 
No,no battery relocation.I'ma see what I can do tomarow.

I found somethin that could potentiolly be a problem.Whatever that little ruber boot with the 2 wires running to it is(righ tnext to the oil pressure sensor,might not be properly connected,as my brother was the one that disconnected most of the motor and he just cut those and we re taped them,but 1 of the may just be the oil pressure sensor wire.I'ma see if I can find some diagrams or somethin and mess with it.Untill tomarow.
 
Well still no luck.The resistro box is still making a constant huming/grinding type noise.We tried replacing the resistor box and it still makes the noise.Also 2 of the plugs were mixed up,but hwne switched it didn't make any difference.The video I took didn't do any good since it didn't pick up the sound,so I have to wait till my brother gets of work so I can get his keys off him and try to take a sound clip.

I think none of that matters though,as we found out the car isn't getting any spark,and we're not really sure why.The 2 dizzy wires are connected like instructed and all,so I'm really not sure what the problem could be.I'm to the point if we don't find the problem within the next few days I'm just gonna say screw it and go through and re-do all the wiring I did,whcih I REALLY don't want to do_Or maybe I'll go get an the inside the car section of the wiring harness and just swap that into it,even though it's gonna be a pain in the ass.

If you guys have any suggestions on anything,or maybe why it's not getting any spark,lemme know.Thanks guys.


EDIT:The main relay is making the wierd noise,not the resistor box,my mistake for not cathing that
 
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