alright so i got a 2001 honda accord with an auto and i want to convert it back to obd1 so i've looked all over the place and everything said only meant for 5 speed and so i did some more research and came to the conclusion that i only have one single unit that controls everything ok so i'm thinking that the ones made for 5 speed could work on mine but not too sure so anybody help me out with this problem and the reason that i'm tryin to do this is because the one that i looked on rywire for was like 300 bucks yea screw that

 

Just buy the harness that is labeled OBD2B-OBD1 for your engine or car whatever and then trim a little tab with a razor blade off the the one plug that doesnt plug up. Shouldnt spend more than $100. If you need one, I have one. We did this to a car about 6 months ago that I tuned. didnt have any issues. Car was orinigally an F22 auto that we put an manual conversion and OBD1 chipped ecu into. There are other things in the auto car that will need to be modded as well.

 

hm yea that helps me out alot can you tell me about the things that needed to be modded much thanks putting a g23 in my car and almost done just gotta do the wiring

 

are you keeping the auto or are you doing a 5 speed conversion? If keeping the auto, then not much needs to be done at all. simply remove and replace. If doing auto to manual conversion then you will need the pedal assy out of another 5 speed car, you will need to do one of two things, either grab the entire interior harnessand cluster out of same car or re-use yours and take the auto selector that was in the shifter pedastal and put it in neutral and tuck it away some where so the car will be able to crank other wise it thinks its in drive or otherwise then it wont crank and run. There are some really good detailed pictures on here and on C-Speed racing how to section. Just remember, your car was OBD2 so you will need to pass all the same emmissions laws an OBD2 car did. Its technically illegal in most states to convert back to obd1 or put an obd1 engine into an obd2 car.

Once you are all done, hook up the ecu and crank the car, check for leaks and then let the fan come on a few times. Then go set the timing at the distributor with a timing light. They are almost always off by a bit. Then go for test drive.

 

i'm planning to keep the auto for now so for now auto and what do you mean remove and replace. the ecu?

 

when you said you are going back to OBD1 I assume you are going to change the ECU to OBD1 otherwise I have no idea what else you were trying to accomplish. By purchasing the OBD2-OBD1 harness you will need and OBD1 ECU and you will need to trim the tab that I mentioned on the harness to get it to plug in for your automatic harness. Be sure to get the correct ECU as some were manual and some were auto ecu's. after that, there isnt much else to do, except crank it up and check the timing. Your OBD2 port under the drivers side will no longer work for scan tools or emissions checks, but the car should drive fine provided you have a working O2 sensor.

If something comes up that doesnt seem right, post it up, but other than the above, you should really just be able to get the harness and ecu and be done.

 

alright thats a big help thanks thanks yea i got the ecu already and it's for auto so thanks thanks

 

Hey guys. I am looking at doing something similar. I have an 02 accord, I want to convert to obd1 but keep it auto. I have been working with all kinds of conversion tables, but an obd1 tcu can not control my obd2b transmission. Are you suggesting I can buy and obd2a to obd1 harness and modify it to connect into my obd2b transmission?