DX and Si
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Joined: May 2002
Posts: 9,814
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From: Granada Hills, Ca, USA
Re: (Mefain)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mefain »</TD></TR><TR><TD CLASS="quote">my car had a SOHC vtec motor in it...so i believe the wiring had been swapped...there is a resistor box if that helps </TD></TR></TABLE>
The DX and SI have totally different harnesses.
Most likely you have a DX engine harness that has been modified to support the MPFI and VTEC.
The Si engine harness doesn't work with the DX underdash harness. You would have to change out your entire underdash harness to run the Si engine harness. People have done that before. It's a complete pain int he butt from what they say.
The DX and SI have totally different harnesses.
Most likely you have a DX engine harness that has been modified to support the MPFI and VTEC.
The Si engine harness doesn't work with the DX underdash harness. You would have to change out your entire underdash harness to run the Si engine harness. People have done that before. It's a complete pain int he butt from what they say.
Joined: Feb 2004
Posts: 3,411
Likes: 2
From: Somewhere, Ontario, Canada
Re: (4drEF)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 4drEF »</TD></TR><TR><TD CLASS="quote">
The DX and SI have totally different harnesses.
Most likely you have a DX engine harness that has been modified to support the MPFI and VTEC.
The Si engine harness doesn't work with the DX underdash harness. You would have to change out your entire underdash harness to run the Si engine harness. People have done that before. It's a complete pain int he butt from what they say. </TD></TR></TABLE>
ALWAYS modify the harness that CAME WITH the car from the factory.
The DX and SI have totally different harnesses.
Most likely you have a DX engine harness that has been modified to support the MPFI and VTEC.
The Si engine harness doesn't work with the DX underdash harness. You would have to change out your entire underdash harness to run the Si engine harness. People have done that before. It's a complete pain int he butt from what they say. </TD></TR></TABLE>
ALWAYS modify the harness that CAME WITH the car from the factory.
Member
Joined: May 2003
Posts: 2,157
Likes: 2
From: Saint Joseph, MO, USA
Re: (4drEF)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 4drEF »</TD></TR><TR><TD CLASS="quote">
The DX and SI have totally different harnesses.
Most likely you have a DX engine harness that has been modified to support the MPFI and VTEC.
The Si engine harness doesn't work with the DX underdash harness. You would have to change out your entire underdash harness to run the Si engine harness. People have done that before. It's a complete pain int he butt from what they say. </TD></TR></TABLE>
actually, all you would have to do is completely repin the main plugs, move ECU pins C1 & C1 to B10 & B12, and connect 2 wires to C1 & C2 for the cylinder sensor in the MPFI distributor. Basically, all the same things as a normal multiport swap except for repinning the main plugs on both sides of the engine bay, instead of just running a couple of wires around the plugs or repinning a couple pins.
Modified by 91civicDXdude at 7:34 PM 7/13/2004
The DX and SI have totally different harnesses.
Most likely you have a DX engine harness that has been modified to support the MPFI and VTEC.
The Si engine harness doesn't work with the DX underdash harness. You would have to change out your entire underdash harness to run the Si engine harness. People have done that before. It's a complete pain int he butt from what they say. </TD></TR></TABLE>
actually, all you would have to do is completely repin the main plugs, move ECU pins C1 & C1 to B10 & B12, and connect 2 wires to C1 & C2 for the cylinder sensor in the MPFI distributor. Basically, all the same things as a normal multiport swap except for repinning the main plugs on both sides of the engine bay, instead of just running a couple of wires around the plugs or repinning a couple pins.
Modified by 91civicDXdude at 7:34 PM 7/13/2004
Keyboard Humorist
Joined: May 2002
Posts: 9,814
Likes: 11
From: Granada Hills, Ca, USA
Re: (91civicDXdude)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 91civicDXdude »</TD></TR><TR><TD CLASS="quote">
actually, all you would have to do is completely repin the main plugs, move ECU pins C1 & C1 to B10 & B12, and connect 2 wires to C1 & C2 for the cylinder sensor in the MPFI distributor. Basically, all the same things as a normal multiport swap except for repinning the main plugs on both sides of the engine bay.</TD></TR></TABLE>
Have to stress plug<u>s</U>
You would have to get the Si plug<u>s</U> and run quite a few more wires than it takes to do the DX conversion. There's a whole plug missing on the driver's side isn't there?
actually, all you would have to do is completely repin the main plugs, move ECU pins C1 & C1 to B10 & B12, and connect 2 wires to C1 & C2 for the cylinder sensor in the MPFI distributor. Basically, all the same things as a normal multiport swap except for repinning the main plugs on both sides of the engine bay.</TD></TR></TABLE>
Have to stress plug<u>s</U>
You would have to get the Si plug<u>s</U> and run quite a few more wires than it takes to do the DX conversion. There's a whole plug missing on the driver's side isn't there?
Member
Joined: May 2003
Posts: 2,157
Likes: 2
From: Saint Joseph, MO, USA
Re: (4drEF)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 4drEF »</TD></TR><TR><TD CLASS="quote">
Have to stress plug<u>s</U>
You would have to get the Si plug<u>s</U> and run quite a few more wires than it takes to do the DX conversion. There's a whole plug missing on the driver's side isn't there?</TD></TR></TABLE>
there is no extra wires. I just did a multiport swap for my brother in his 88 DX 4 door. It goes like this...
on the driver side strut tower, the one large main plug.. you can remove the orange wire and a black & yellow wire that both go to the DX's tandem valve, which MPFI injection does not have. there are already a couple of empty holes. use the existing red and yellow injector wires in the harness, and add a brown and blue wire for the other two injectors. then of course you have to hook both yellow-with-black-stripe wires up to the resistor box power. that takes care of the fuel injector problem and the driver side strut tower.
now onto the distributor. After swapping pins C1 & C2 to B10 & B12, you must pin two wires (blue-with-yellow and blue-with-green if you want to stay "stock") to C1 & C2. run these two wires through a grommet in the firewall, along the engien harness, up to the passenger strut tower. Here is where you encounter a *very* small problem. the passenger side main plug doesnt have any free spaces. How to solve this? simple. get any male and female 2 prong plug and pin it. I personally used the small plug that runs power and ground to the purge cutoff solenoid, since its 2 prong and i have about 20 extra ones laying around.
to recap, you can use the Si engine harness, but if you choose to repin the DX car harness to Si plugs you will have no problems. If you choose to repin the Si harness to the DX harness, you will have to make a second plug on the passenger strut tower, which if you are going through all that trouble just to save a couple minutes of wiring in the resistor box, then you have issues.
what im saying is, you *can* use the Si harness, but its really not any easier than just modifing the DX harness. the only thing you will save by using the Si harness is the 3 seconds it takes to depin and switch the two outer TPS wires and repin them.
Have to stress plug<u>s</U>
You would have to get the Si plug<u>s</U> and run quite a few more wires than it takes to do the DX conversion. There's a whole plug missing on the driver's side isn't there?</TD></TR></TABLE>
there is no extra wires. I just did a multiport swap for my brother in his 88 DX 4 door. It goes like this...
on the driver side strut tower, the one large main plug.. you can remove the orange wire and a black & yellow wire that both go to the DX's tandem valve, which MPFI injection does not have. there are already a couple of empty holes. use the existing red and yellow injector wires in the harness, and add a brown and blue wire for the other two injectors. then of course you have to hook both yellow-with-black-stripe wires up to the resistor box power. that takes care of the fuel injector problem and the driver side strut tower.
now onto the distributor. After swapping pins C1 & C2 to B10 & B12, you must pin two wires (blue-with-yellow and blue-with-green if you want to stay "stock") to C1 & C2. run these two wires through a grommet in the firewall, along the engien harness, up to the passenger strut tower. Here is where you encounter a *very* small problem. the passenger side main plug doesnt have any free spaces. How to solve this? simple. get any male and female 2 prong plug and pin it. I personally used the small plug that runs power and ground to the purge cutoff solenoid, since its 2 prong and i have about 20 extra ones laying around.
to recap, you can use the Si engine harness, but if you choose to repin the DX car harness to Si plugs you will have no problems. If you choose to repin the Si harness to the DX harness, you will have to make a second plug on the passenger strut tower, which if you are going through all that trouble just to save a couple minutes of wiring in the resistor box, then you have issues.
what im saying is, you *can* use the Si harness, but its really not any easier than just modifing the DX harness. the only thing you will save by using the Si harness is the 3 seconds it takes to depin and switch the two outer TPS wires and repin them.
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