Okay, heres the deal. I bought a 91 CRX with no engine or tranny. The car is a DX (I think) I know for sure that it is NOT a SI. Now whe I bought the car It came with an A6 motor in peices, and the SI wiring Harness, but NO DX Harness. Now I figure that I'll wind up taking off injector plugs and the resistor box off of the SI harness and retrofitting them onto the car for my MPFI swap. I'm putting in a B18a. So I didn't have the DX Harness from buying the car. So I just went to the Salvage yard today and bought a harness off of a 90 CRX DX but the harness has an extra 11 plug connector that my Chassis doesn't have. (See Picture) It "Y" off right before the master cylinder plugs on the car I got it from but my car doesn't have this plug at all. Does this make my car a HF or what am I missing here?

Please help me out here.

 

Since your car is an 88dx it has the rectangular plug instead. it is visible in your picture. You need to purchase the 88dx harness and doe the mpfi conversion.


http://www.redeyefabrication.com

 

My CRX isn't a 88 its a 91. And the plug in the picture came from the junkyard car. and it's round. The wires look kind of like this.

/ / / /
/ / / / /
/ / / /

Any other Ideas?

 

there is one that comes from the engine bay (engine harness..) and there is one that comes from the subharness (from inside). Correct me if i'm wrong, i did this a while ago.

i was dealing with the same problem on my car. i'll take some pictures when i get home.

 

I understand now. The rectangular plug is 91 spec and the round plug is 88 spec. So all I need to do is to clip the 88 Chassis side plug (Male end) and splice them together. right? I'm enjoying the help guys thanks.

 

There is no difference in plugs from 88-91. ALL DX's, same plugs, ALL Si's, same plugs.
The difference in the plugs is determined by what engine came in the car originally. IF your car IS a DX, you need to convert to MPFI, by splicing in the injector wires and the resistor box from the Si harness INTO the DX harness and do some rewiring at the ecu plugs. And adding the TDC sensor wires.
HTH

 

Okay so I plug in the rectangular plug from the SI Harness and forget about the round plug completely?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dividebyzero &raquo;</TD></TR><TR><TD CLASS="quote">

Okay so I plug in the rectangular plug from the SI Harness and forget about the round plug completely?

</TD></TR></TABLE>
You can NOT use the Si engine harness in a DX. Period. End of story.

 

I'm not trying to use the whole harness If I were why would I have gone to the junkyard and gotten a DX harness to begin with. So what do I do about the round plug?

 

While I was at the Junkyard there were two EF's one CRX and one Sedan both had the exact same round plug by the Master cylinder. Then I get home and there is no round plug so what does this mean? If all of the engine harness are the same why are they different. I've got the right harness but I've got this 11 plug round harness that doesn't plug into my car at all. I can't do the MPFI swap yet the harness is incomplete.

 

Maybe I wasn't clear. ALL the harnesses are the same between years, ONLY! NOT between models DX=DX , Si=Si, HF=HF, they're NOT plug and play, between models ONLY between years.
What you need to do is.
Splice the 4 injector clips and the resistor box wiring, FROM the Si harness into INTO the existing DX harness you got from the junkyard. Add the CYL wires to the DX harness, swap wires at ECU inside the car, done.

 

Okay,

I'll trust you on this and go for it. I won't have the engine in for another month (or less) but I'm trying to get everyhting sorted out beforehand.

Thanks.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dividebyzero &raquo;</TD></TR><TR><TD CLASS="quote">Okay,

I'll trust you on this and go for it. I won't have the engine in for another month (or less) but I'm trying to get everyhting sorted out beforehand.

Thanks.</TD></TR></TABLE>
You don't HAVE to trust me. LOL Just try this thread https://honda-tech.com/zerothread?id=719454
And search MPFI swap in archived topics.
HTH

 

I think that's some incorrect information. I know for a fact that a 88 has a different harness than a 89-91 for sure. An 88 si, does not have a round plug on the driver's side. both plug's are rectangular, as where 89-91 models have either a singe round(dx) or a round and a rectangular(89-91).


http://www.redeyefabrication.com

 

Well, to try and clear this up for you, the ONLY one that doesn't fit is the 1988 SI, that's it. ALL, the rest fit as I said above ALL 88-91 DX's and ALL 88-91HFs use the same plug arrangement and the 89-91 Si's do as well. They will all interchange with each other.,
BUT the plug arrangements are irrelevant. They would NOT BE interchangeable EVEN if the plugs DID match, as the wire pin locations inside those plugs would not match. You CANNOT exchange engine harnesses between HF's, Si's or DX's. You MUST use the harness that goes with the chassis NOT the one that comes with the engine you are swapping.

 

Okay Full stop!!!!!!

I've just spent the last three hours with my dad checking continuity between wires. I plugged in my SI harness and the wires MATCH COLOR FOR COLOR. I go inside the cabin and I HAVE a ORANGE wire at B10 and a WHITE wire at B12. Both have cont at the dizzy plug. I have cont betwwen all FOUR of the Injectors at A1 - #1 A3 - #2 A5 - #3 A7 - #4 again colors match exactly. My computer has all of the right terminals in all of the right places.

Is my car a HF or did someone else swap the ENTIRE CHASSIS Harness over.
When I bought the car from the guy he said that he originally wanted to put a Big block Chevy engine between the fenders and make it into a straight liner. Now I don't know the cars history past that. The wires seem to be intact and not molested in any way.

Also.

I looked at the dizzy plugs on my 91 Integra and the colors are different than the SI Dizzy plugs is this a problem? Because I'm going to use the OBD-0 Dizzy from a 90-91 Teg on my B18a. At this point should I consider my car a DX with an SI Wireing system?