91 CRX HF D16B6 Swap to 90 SI D16A6..Help!!

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josh18

Junior Member
I needed to ask for some help on this wiring. Im switching from a 90 crx hf, to a 90 crx si motor, D16B6, to a D16A6. I am trying to use the SI wiring harness that is still intact and on the SI engine, it fit right in, but it keeps throwing code 15, i've exchanged distributors out with a known good one, same code 15, Igniter. is there a way i can do some pinout work and switch a few wires, like the crank angle, or cylinder position sensor, or do I need the Hf wiring harness? Please... can anyone give me some Knowledge about this swap? Will the same ecu work as well? both are manual trannys. I pulled the plug, and when i first turn the ignition switch to the run position, i get a spark from the spark plug, but nothing while i am turning it over. wont start, feelin sad, guess i need to call ol dad........ THX.
 
does anyone know what modifications i need to make to the HF wiring harness so it will work with this SI, or does it just plug and play?
 
Originally posted by josh18@May 31 2004, 02:46 PM
does anyone know what modifications i need to make to the HF wiring harness so it will work with this SI, or does it just plug and play?

you need to use the HF harness - all of the wires are in different locations in the connector on the Si where it plugs in at the driver's side shock tower, next to the resistor box - the HF harness is plug and play - you will have one connector left over on the HF harness that went to the EGR lift valve, which you won't need for the Si - you will have a fast idle control valve on the back of the Si intake manifold on the driver's side which isn't on the HF, so you won't have a connector for it - just leave it with no connection (plug the vacuum lines on it) as it isn't necessary for the car to run - the fast idle control valve only works when the ambient air temperature is below -10C (14F) and just speeds up the idle a little to compensate for the low temperature - it isn't on 88 Si, only 89-91 - you cannot repin the Si harness to make it work - the HF has different wires in the connector (one is for the alternator) which aren't even in the Si harness - they go to a different connector on the Si
 
Hey, thank you for the info. you are exactly right, even with the locations of the plugs!! B) Since i have someone who knows about this, i hope you dont mind helping me out with another prob. To make a long story short, It wont fire.
It keeps throwing a code 15, and i cant get any spark. I have tried two different distributors, but nothing. I have a few straggler wires left over, plus i dont think that i have the entire hf harness, missing the injector part, or so im told. My injectors appear to be feeding in from the drivers side, (injector resistor box),
but the si harness had four more wires that were coming from the fuel rack and crossing over to the passenger side. They were green w/white stripe, blue w/ white stripe, and red w/yellow stripe.i had to cut these in order remove the si harness, and i dont have a clue as to where they should be hooked up.One more thing, pleaseeee, i have three more wires from the drivers side , back of the intake, (as well as the aforementioned plug w/o a home) :D , that are cut and hanging, they are yellow, white and blue w/ yellow stripe. I sure hope you can help me, i cant seem to find the wiring diagram for a 1990 d16a6 anywhere.the manual cuts off at 1987. Thanking you in advance, :worthy: im gonna hope for some spark from this thing next round, Kid sure wants his ride to run. I been there too!! thx alot.
 
i just put a hf motor into my si body i had to use the si dizzy intake and ecu
the harness on my hf motor had to be changed i used one off of a dx and my car runs great slow but great ((gas mileage)))
the harness on the hf would not run on the si on the pass side shock tower the wires are diffrent there to chris
 
Dragntoys,
Interesting you did that...I'm doing the exact same thing. Black 90 Si conversion to HF.

What kind of gas mileage are you getting? I'm hoping for 50mpg. I kept the Si fuel tank and Si rims...but expect that going to the 8gal hf tank and 13 in donut rims would help increase fuel efficiency.

So you kept the Si Ecu? I have Hf Ecu, and i'm 90% complete on the wiring adaptation. That yellow wire from the EGR value...does that just go to the ECU?

I have the black box of emission sensors...I also found an instrutment cluster with the 5k redline from another hf.

I might have you send some picks...do you have a website with an documentary of your swap?

Marc
 
why not justy get an HF instead of swap? My HF is fine but i get a 12 code on my ecu. The internet has told me that code 12 has something to do with the egr system either its failing or the wires are loose or coroded. However i don't belive its failing becasue it drives fine and i still get my 40 mph :p but my idel sometimes varies as it likes to bounce. I have not had much of a problem with that since i switched altinators. MY MAIN problem is my battery keeps dieing after a few days And i would like to belive its the egr wires grounding out. But it could also be the engien ground or other wires too. (i hate wires but loves stereos.) Now I havn't looked too hard but my haynes manual is not very helpful on this subject. It says that there is an A part and a B part of the egr. Makes sence i suppose but the location or either is unknown to me.

If anyone has a sugegstion i'd be happy to try it. But I just wanted you all to know I respect the HF swap choice lol. And i wanted to turn my HF into a vtec but my plans changed after i found out the other rex fall short in mileage.

Later.
 
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