A swap dash wiring question!

[Texas240sx]

I just put a 96' engine in my 89'. I am connecting the 96' harness to the s13 wiring in the dash. There is a dash harness plug on the 89' right behind the glove box which should be white or on some years brown that was used with the 89' harness. It has about 13 wires coming from it. I found some info on color matching it to the new harness.

My question on that is where do I splice into on the 96' harness from the 89' dash plug?

1. Do I splice into the main plug that connects on the ecu itself.

or

2. The other plug also on the 96 harness in the dash area (a white one near he ecu plug) which has about 25 wires and looks like a minature ecu plug and has another little white plug with about four wires coming from it. This one doesn't plug into anything so I thought it would be okay to splice into since it's just a plug hanging that doesn't connect into anything.

Also about the plugs next to the battery ( e10 and e9)! Do I run line from the plug under the dash to those. I was looking at the drawing diagram on heavy throttle. http://heavythrottle.com/ Its under Install FAQ then click on electrical wiring then scroll down to the drawing. I am using a 96' harness and dont have the f10 or f8 plugs. I thought the best thing to do is run the lines from under the dash through the firewall to the s13 plugs near the battery. Is this right?

I know this forum is filled with people who know, and hopefully I will also know soon.

Thanks for any help or info on this!

[Texas240sx]

Anyone know if I splice into the main connector on the ecu itself! Thanks!

[NISTECH]

this is a very intricate task you are trying to achive. the 96 is a completely different computer system. one is obdII the other is obd I. the 2 systems function totally different from one another. why did you swap to a 96? are you looking for horsepower improvement or did you just have an engine failure. if you find any one who can help you they would of had to do this exact change or be extreamly familier with both years of the car. your best bet would have been to do a 100% exchange of the entire wiring to the year engine your installing. this would be a major trial and error attempt which could become quite expensive if you start crossing computer/ sensor wires.

[Texas240sx]

Yeah my old engine was blown, so I got this set up real cheap from a friend. I pulled everything from the 96'. Sometimes I feel like just going and getting s13 doch parts like the intake, ecu, and harness. I have spent many hours searching the web and the harness wiring seems rasonable. I have got bits and pieces from sites. I have an 89' harness and wanted to cut the dash plug (one behing the glove box) and mate it into the wires coming from the ecu plug. Also run the 89' harness pieces by the battery area to under the dash and then splice those wires on to the ecu plug according to colors. I would use the entire 96' harness and the part of the 89' harness thats needed . Such as the fuel pump relay wire and ecu relay wire, and ignition wire. I will run that part of the 89' harness back just like in an sr swap. I want to try it, but wondered if it sounded like a far fetched idea or an idea that might work.

[240doc]

I am currently in the process of installing a 97 240 engine into a 89 chassis. here is where my story is different: I have completely swapped wiring harnesses from 89 to 91 dohc harness (I mean every wire in the car!). When I bought the 97 engine I got the engine bay harness and compared it to the 91 harness. for the most part they are the same, fuel injector, AAC, FICD solenoid, knock sensor all plug up with the same connectors. you will have to either rewire or exchange coolant temp sensors (different plug). the 97 harness doesn't have provisions for the swirl control solenoid because the s14 doesn't have that setup on the intake. the distributor on a 97 has more wires than the 91 harness and the throttle position sensor is totaly different from the 91. I checked to see if I could use the 97 TPS if I just wired it to the 91 harness, BUT the two have different resistance values at throttle movement so I believe that the ecu will not understand wtf is happening and might not let the car run. I ended up swapping out throttle bodies (yes the rod that the TPS is operated by is different from 97dohc to 91dohc. I removed some of the 97 only vacuum solenoids (left the one that controls egr) and switched the exhaust manifolds to the 91 ( the 97 manifold is setup for a single downpipe whereas the 91 has two)

sorry this is so long but there is some valuable info here, and I have learned alot through all of this. for your case of using a sohc wire harness for a 96 engine: the sohc and s13 dohc harnesses are very similar if at all possible I would try to make the sohc harness work on the 96 engine. you will probably have to swap some parts off of a 91-94 to get around the obdII & I stuff. I beleive you could then get a ECU from a 91-94 to run the engine with the sohc harness. I have a complete 89 harness (front to back of car), a 97 engine bay harness, freshly rebuilt sohc with 0 miles, a running 91 ka24de, 89 FSM, 91 FSM, a few rare HICAS parts and a ton of other nissan junk!-- I think I should open up a salvage yard!

wish you luck!!

[Texas240sx]

I think I am gonna have to go that route! As soon as you get it running let me know what you did exactly! I have Sunday off so I am gonna give the 96' harness a try with some pieces of the 89' harness! If not I'll be going to the salvage yard for some s13 dohc parts! I hope it works though! Some one on club240.com told me he did it, but now that I have some question I can't find his email address!

[bvanev]

I swapped a 93 into a 89 with very little trouble. That little harness under the dash...get a FSM for both years, most dealerships will let you make copies, or at least make notes, and ring out the wires, then just mate them up. I don't have all the specificsc, as it was over two years ago now. Just take your time and be methodical about what you are doing.

[Texas240sx]

I have the pinout guide for the 96' ecu that I found off some website. Then from reading how to wire splice an sr harness into an 89' gave me an idea of where the wires are right by the battery. They color match with the 96' ecu also. To me it really sems like it will work, but I am not sure. Seems just like extending wires from the ecu to the battery area. Hopefully I can get it started with the 96' harness.