Hey guys I really hate to even ask this but Im doing an oddball swap, well really just reverse of what most do. I have a 90 honda accord ex with an f22a1 in it and a 93 prelude si 4ws that had a h23a1 (popped) motor in it. Well I have the f all bolted in with the h trans (manual) and h intake bolted up. Where I am running into issues is the wiring, I have the pt3 plugged into the car but the engine side of the harness is different from the fs wiring harness. Wth do I need to do? I have tried reading about the f to h swap but all they say is to use this or that ecu and not what to do to make it work. Thanks in advance guys.

 

So you took the F22A1 from and OBD0 Accord and threw it in the OBD1 93 Prelude or is it in the Accord with the Prelude parts? If that's the case, what wiring issues are you referring to? What engine harness are you using, F or H?

 

Well, I was under the understanding that the accord is obd1, this is the only site I believe that has it listed as obd0 all others say obd1. Anyway I was trying to use the f harness but where it plugs into the main harness that goes through the firewall those plugs are different, also the dizzy wires are different, I think that's due to going from the external coil to internal coil. There is a flat connector on the f harness that the h doesn't have also. Could it be that the prelude might be an actual import? I mean this car says made in japan all over it lol. Thanks again, if I figure out how to post pictures I will.

 

Im sorry it looks like I didn't answer your question, yes i did take the accord motor and put it in the prelude. I have also reconfirmed that it is obd1. It looks like I will need to use the H wiring harness, and wire the distributor plug off the F harness into the H. I got to looking at it and the plugs are nearly identical, all the wires going into them are the same color codes too. Do you think this will work? Man I hope so or I am screwed. Also do you know it the p14 (from the prelude) will work with the F or should I just use the pt3? Thanks

 

Am I the only one who has run into this issue? After reading for hours on different forums I still have not found any info on this, thanks.

 

I'd keep the P14 if I were you. And as far as that car being OBD0 or OBD1, the easier way right now for you to find out is, since you have both cars available, the wiring connectors for the ECU on each car. Do they look the same? Can you plug the PT3 on the Prelude wiring? If so, then it is OBD1 like you said. I thought OBD1s started on 92 models tho, maybe this one since its an EX is different. I had a 90 Prelude that was OBD1 also. Anyways, back to your questions. The H wiring and ECU would be your best option, especially if you're using the H23 IM and injectors. Just take care of the dizzy and give it a shot. Honestly, you're the first guy I've seen doing this setup, ppl always seem to go the H route. But then, the Prelude came with a SOHC F22 as well, so there's definitely a way to make it happen with the proper wiring and ECU. Keep posting your progress, good luck.

 

I think I have a prelude F22 ECU floating around somewhere, I'll try to look tonight. If it turns out that you can't use the F22 ECU you have or the H one doesn't work.

 

Ok guys here is the deal, like I posted earlier the large connector for the dizzy on the f and h are both the same EXCEPT the h harness wont plug into the f dizzy, the f harness WILL plug into the h dizzy. Weird but true, so what I did was took the plug off the f harness and wired it to the h harness since all wires were identical (in color) except the blue wire off the h and I think that it goes to the external coil? You will never guess what? no spark, I have tried both ECUs and still nothing. Yes the pt3 out of the accord will plug into the h harness, I have discovered that when it comes to OBD that honda did some stuff that wasnt really straight forward as far as model years go between different models. I have been doing some reading on no spark issues but have found very little. You would be amazed how many forums I have read in the last 2 week, and how many threads end with now avail. That Kinda makes me mad to read a two page thread and it just ends with nothing, so I try not to do that myself knowing my problem and solution may help someone else. If you guys have any idea why I might not be getting any spark please let me know. Thanks again.

 

@ typemismatch I meant to say thanks for the offer on the ecu I hit the post button to quick lol. If it turns out I need one then I can pm you if thats cool?

 

the blue wire is the tach drive and needs to be connected at the distributor. The only modification you need to do is on the plug that used to go to the coil. Take the yellow/black and yellow wires and splice them together, this feeds power to the internal coil of the distributor.
GL
Mike

 

i have a 0bd1 h22 harness if you need mint no cuts pm me if interested

 

Well it runs, I didn't have the radiator in it so I didn't run it for more than a minute. It seemed to be idling at around 2000 rpm, cold start idle or is there somethin that I might be missing? @ mherkamp, the plugs for the actual dizzy were different, there was plastic spacers in the one for the h harness that would not allow it to plug into the f dizzy. What you said about the other two wires though sounds right because I got it to run after plugging the coil into the harness. I did this beacause it was the only wire with a 12v reading with the ignition in the on position, and thought it maybe the feed wire. Now just to get the coolant and ALL the vacuum lines and the halfshafts back together and see how it drives. Does anyone else have an opinion on what ecu to run? I got it to start with the p14 but man even the minute I ran it seemed rich. Thank you guys so much for all your advice/knowledge and offers on parts. Hopefully in the near future I will be able to give some usefull info back.

 

Sry I wasn't clear, I meant the only FURTHER mod you need to do. Apparently, the f22 wiring harness will plug into an h22/h23 dist. no problem but not the other way. Really glad to hear you got it running. BTW, the external coil is better than the internal one because the internal one has a tendancy to fail. I think there is a mod to do this, since you have all the parts from both cars. Thats why Honda went to the external in later years. Just my .02, FWIW. GL and enjoy! RU planning boost? Iron sleeve f22 FTW!
Mike

 

I just put the radiator in and filled it up, let it run for about 10 minutes and played with the timing a bit (I dont have a light) but the idle came down to around 700 rpm or so. It had a slight miss about every 10 seconds or so. I need to get a wideband so I can see if the p14 and the h I/M has it running to rich, guess I could run it for a bit longer and try to read the plugs, I have gotten fairly good at that from working on 2 strokers lol. I have about $1000 worth of exhaust still left on the accord so hopefully I can make that work somehow too. Oh and @ mherkamp I hope you dont think I was trying to be a smarta*# cus I wasnt and when I went back and read my post I was like oh no that prob didnt sound to good to some. And yes I am planning on boost later on, I do like having around 180 hp N/A though. I just wanna save the money and do it the right way, no ebay crap for me. The motor has the head milled and a cam regrind in it, and I think we went 2mm over on the valves. Anyways guys I really appreciate all your help, any more suggestions send them my way. I got the accord for free and only paid $500 for the prelude so Im pretty much willing to try anything so long as it doesnt blow up lol. Later.

 

No offense taken, just glad you got it going!
Mike

 

ha I wish I had noticed earlier that the power steering pumps were different, well the high pressure line on top is and how they mount is different. Guess I will be under the lude tomorrow to change that. Both alternators are bad and I need to buy a battery. Man Im just ready to drive this thing already lol.

 

Just rip out the PS, no need for excess weight/stuff to go wrong! The write-up on here on how to do it is actually really good.

 

Just thought I would throw an update up. I took the p/s line from the accord and put it on the prelude. For some reason I think im hearing a slight missfire, and throwing cel codes 41 and 10, might have got the t/belt to tight too, it sounds like a frigin pressure cooker lol. Any suggestions on the codes would be greatly appreciated (I know what they are) just didn't know of any little tricks someone may have up their sleeves. Thanks again guys.

 

Code 41 probably means your O2 is fried, get a new one and see if that fixes it. Also, are you running an internal coil dist. with an external coil plugged in also? Could be part of the problem.

 

Yes im running the internal coil, I soldered the two external coil wires together.

 

Well i got it all together license and insurance, drove it to the muffler shop to get the flex tube replaced $140 I about sh!% myself. Well Im throwing CEL code 23 now, pulled up as a knock sensor? To my knowledge neither the h23a1 or f22a1 had knock sensors, little help here fellas thanks again.

 

Yes, h23 has a knock sensor, what ecu are you running? The p14 ecu will be looking for that sensor.

 

Yep running the p14, gonna go do some reasearch on a workaround thanks again man you have been a big help.