Need Help! Obd2b engine/harness/ecu in Obd2a Car

Justinmaccc

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Okay so apparently i have the worst luck in the world or I'm just too dumb to research before making purchases. Long story short(kind of) I bought a 99 civic with a 2000 b16a2 engine in it about 3 weeks ago. Unfortunately after driving it for about a week and a half i was hit by an idiot that ran a red-light in the rear quarter panel. Although this sucks, i decided that not all was lost as i could just buy a shell and swap the motor. Well after looking for a short time on a local honda Facebook page i found a very clean 98 4 door and decided to buy it so i could get back on the road as soon as possible. So this weekend, a friend and i decided that we were going to get themotor swapped and all would be great. (Im sure most of you know where this is going) We got the motor into the 98 and it started right up no issues what so ever.....until i looked at the cluster and the tach and speedo were not working. Well that didn't make sense to me because it all worked just fine less right before we pulled the motor from the 99. and i know the motor was installed right. So i turned to the internet where i soon found out that i tried to put an obd2b engine into an obd2a car i suppose thats what i get for not doing the proper research before putting an engine from a later year into an earlier model car. But i shrugged it off because "its only one year difference, how much could they change?". I should also add that the 98 car came with a GSR engine harness which I'm assuming is obd2a Im not sure if this can be used or not.

Anyway I'm here because id really like to know the simplest way of making this motor work in the 98 without spending a ton of money to do it.

I know i could pull the under dash harness from the wrecked 99 civic and essentially convert the obd2a car to obd2b, but thats not exactly the easiest thing in the world to do and id like to avoid it if possible.

Any help is very much appreciated, id like to make this car drivable as soon as possible.
 
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dancam

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This hasn't been up that long... Most people aren't on here every couple hours. You might want to try posting this in other forums as well...
Anyhow, i dont know any more about it than you, sorry i cant help.
Looks to me like you have 2 options. Figure out how the wiring worked on the car before and either wire the speedo and tach separately or maybe the sensors off the other engine can be put on this one and wired directly?
Or can you put the other instrument cluster in the car?
Or get real messy and remove the computer and wiring from the other car, chop off everything unrelated to the instrument cluster and related sensors and install it.
Hopefully someone has a better idea for you, just be patient.


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mymmeryloss

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What are your plans for the car?
 


Justinmaccc

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Which car? the 99 is getting parted out. i still have most of the parts though. and the ex will be my daily but i do plan on boosting it eventually.
 

mymmeryloss

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If you plan on upgrading y not just go standalone now
 

Justinmaccc

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Ive narrowed it down and i think i have two choices(that do not involve converting to obd1). keep in mind I've read ALOT of forum responses on the subject and everyone was giving different answers so i don't know what will actually work and what will not

1.) buy a 96-98 ex harness(d16y8), modify it to work on the b16,and then buy an obd2a to obd2b jumper harness so i can still run the b16 p2t ecu. (correct me if I'm wrong but I'm pretty sure this will work)

2.) I could gut the interior harness and dash harness from the 99 ek and swap it into the 98 ex. this method will without a doubt work because it would essentially be a 98 car with 99 brains. An obd2a to obd2b COMPLETE car conversion.

The 1st option seems the easiest but also requires the most money which I'm kind of tight on right now.

the second option would require no money at all (seeing as i still have both cars and everything needed to do it) but i read that its extremely tedious in fact i called a local honda repair shop and they said that they didn't even want to attempt it unless i was ready to spend a lot of money.

Anyway the reason I'm here is because I want to know what I'm going to be dealing with if i go ripping into the internal wiring of the cars. What makes the swap so difficult? i found a thread that seems to be some sort of write up on how to do the swap but it is not very detailed. has anyone ever heard of someone converting their obd2a car to obd2b? I just want to know what I'm getting into to make this swap work in my car.

Any help is VERY much appreciated
 
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XpL0d3r

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Merged your threads since they were both pretty much the same thing. If you plan on boosting it you pretty much have to go ODBI to get it tuned.

Anyways, you should just be able to get the ODB2b -> ODB2a conversion harness and be good to go. Reuse the ECU from the crashed car since you know it works with the b16 already.
 

Justinmaccc

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Merged your threads since they were both pretty much the same thing. If you plan on boosting it you pretty much have to go ODBI to get it tuned.

Anyways, you should just be able to get the ODB2b -> ODB2a conversion harness and be good to go. Reuse the ECU from the crashed car since you know it works with the b16 already.

Yeah i figured! still new to this hahaha.
Once its historic or i do my last emissions test ill go obd1 as for now I'm just going to daily drive it the b16 was getting like 30-35 mpg in the 99! I just want everything to work correctly first, can't daily drive if the radiator fan doesn't come on lol.
i keep reading mixed things about just using an obd2b-obd2a jumper harness. some people saying it will and others saying it won't.
i think the jumpers only allow you to run different ecu on the car. like if you wanted run a 99-00 ecu in a 96-98 car you'd use obd2b-obd2a.
I don't think they allow for converting the engine to work with the car.
 

XpL0d3r

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Yeah i figured! still new to this hahaha.
Once its historic or i do my last emissions test ill go obd1 as for now I'm just going to daily drive it the b16 was getting like 30-35 mpg in the 99! I just want everything to work correctly first, can't daily drive if the radiator fan doesn't come on lol.
i keep reading mixed things about just using an obd2b-obd2a jumper harness. some people saying it will and others saying it won't.
i think the jumpers only allow you to run different ecu on the car. like if you wanted run a 99-00 ecu in a 96-98 car you'd use obd2b-obd2a.
I don't think they allow for converting the engine to work with the car.
Gotcha lol. You'll still have to do some wiring but it won't be tht bad.

http://honda-tech.com/honda-civic-del-sol-1992-2000-1/obd2b-b16a2-into-98-civic-ex-wiring-2876117/

See post 6. You have a P2T ECU right? :thumbs up
 

mymmeryloss

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Rewiring the interior isnt hard. Its stupid time consuming especially if you dont want to break anything or hurt yourself :rolf:
 

Justinmaccc

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Gotcha lol. You'll still have to do some wiring but it won't be tht bad.

http://honda-tech.com/honda-civic-del-sol-1992-2000-1/obd2b-b16a2-into-98-civic-ex-wiring-2876117/

See post 6. You have a P2T ECU right? :thumbs up

Yes sir! i think I'm going to just buy the y8 harness. but I'm gutting the coupe to part it out so ill just keep the dash/interior harness just in case i ever do decide to convert to obd2b. I'm doing the 99-00 dash swap anyway so once i get that far i might just decide to convert it all. I appreciate all the help and ill let you guys know how it works!
 


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