anyone made their own OBD0->OBD1 harness before?

[newaccorddriver]

like the topic states, im just trying to find out the level of ease to make your own harness, im considering converting to OBD1 soon


EDIT: i should also take the time to ask, do i need to have the second O2 sensor like the 88-89 accords have?

[SteveDX89]

No, you will have to buy a 4-wire O2 sensor like an OBD 1 car has. They're usually about $100. Converting to OBD 1 shouldn't be too difficult if you have the conversion harness. If you make your own, which seems like you want to do, that will be difficult.

[newaccorddriver]

No, you will have to buy a 4-wire O2 sensor like an OBD 1 car has. They're usually about $100. Converting to OBD 1 shouldn't be too difficult if you have the conversion harness. If you make your own, which seems like you want to do, that will be difficult.


im not too sure about how to hook up the 4wire O2 sensor, but it just seems like hooking 1 wire to the ECU, 1 to a ground, 1 to another ground, and 1 to the coil or something. ive read it somewhere on hondatech i think...

as for the conversion harness, if i have both the OBD0 and OBD1 wire readouts(or whatever thats called), couldnt i construct my own harness or does it not work that way? im trying to make my own to save some money, my last resort would be to go out and buy one...

[SteveDX89]

as for the conversion harness, if i have both the OBD0 and OBD1 wire readouts(or whatever thats called), couldnt i construct my own harness or does it not work that way? im trying to make my own to save some money, my last resort would be to go out and buy one...

Yes, it works that way but you have to add a bunch of stuff as a subharness and it's not as simple as you think since they have different names for the wires. It's not like it's impossible to do but if you're a newb to this kind of stuff, it will get difficult. I think I'm gonna try making my own but I'm only about 30-40 percent confident I can do it.

[newaccorddriver]

Yes, it works that way but you have to add a bunch of stuff as a subharness and it's not as simple as you think since they have different names for the wires. It's not like it's impossible to do but if you're a newb to this kind of stuff, it will get difficult. I think I'm gonna try making my own but I'm only about 30-40 percent confident I can do it.


i think im gonna try making my own first and then probably go out and buy one... just curious, is the 4G accord ECU any good when i convert? ive read the OBD1 thread and it recommends the P75, but i think those are hard to come by(in canada atleast...)

EDIT: isnt the jkobd harness just 1 piece or do they include a sub harness

[SteveDX89]

EDIT: isnt the jkobd harness just 1 piece or do they include a sub harness

The subharness is probably already connected to the ECU plugs. The other ends of those wires need wired up manually. They are the additional wires for the O2 sensor, etc.

[newaccorddriver]

They are the additional wires for the O2 sensor, etc.

so ill have to run 2 O2 sensors then? the 4wire O2 sensors just for heating it up quickly.

[guaynabo89]

soldering all the conections and getting the plugs is a pain in the ass. better off buying a harness and changing it according to what ecu setup you have.

You dont sound to familiar with this type of project and it is fairly involved. not to mention finding shielded wire can be a pain.

Im still trying to figure out what to do about the vss signal to the ecu which is still throwing the vss code. im researching it right now and hopefully it will be an easy fix. The accord speed sensor isnt like the crx one posted in the link in the obd1 thread. our gauge cluster has a sort of amp that completely sends the wrong type of signal to the ecu.(voltage and pulse wise)

[SteveDX89]

so ill have to run 2 O2 sensors then? the 4wire O2 sensors just for heating it up quickly.

Read my post again. Not only did I say you need 1 4-wire 02 sensor earlier in the thread. The second time I used the word sensor, not sensors. Sensor is singular meaning 1.

[Legend_master]

i think im gonna try making my own first and then probably go out and buy one... just curious, is the 4G accord ECU any good when i convert? ive read the OBD1 thread and it recommends the P75, but i think those are hard to come by(in canada atleast...)

EDIT: isnt the jkobd harness just 1 piece or do they include a sub harness


Jkob makes only sub-harnesses and Rywire makes engine harnesses

[Oldblueaccord]

like the topic states, im just trying to find out the level of ease to make your own harness, im considering converting to OBD1 soon


EDIT: i should also take the time to ask, do i need to have the second O2 sensor like the 88-89 accords have?


http://www.locashracing.com/store/

have you tried this guy hes been around since honda-hybrid.com days.


wp

[carotman]

You don't need to have a 4 wire O2 sensor if you disable the O2 heater in the ECU Rom.

The purpose of converting to OBD-1 is to have a tunable ECU that will run a custom program.

However, if you use a Stock OBD-1 ECU, wou will need the 4 wire O2. There is no point to convert to OBD-1 if you use a stock ECU tough.

[newaccorddriver]

Read my post again. Not only did I say you need 1 4-wire 02 sensor earlier in the thread. The second time I used the word sensor, not sensors. Sensor is singular meaning 1.


what i meant was, the 88/89 accords use 2 O2 sensors, and from what i know, some cars use 2 of them, i was just wondering if i had to run 2 of them to make my car OBD1

[newaccorddriver]

You don't need to have a 4 wire O2 sensor if you disable the O2 heater in the ECU Rom.

The purpose of converting to OBD-1 is to have a tunable ECU that will run a custom program.

However, if you use a Stock OBD-1 ECU, wou will need the 4 wire O2. There is no point to convert to OBD-1 if you use a stock ECU tough.


im converting trying to convert my car to OBD1 in preparation for turbocharging it

[AccordEpicenter]

you could run a 1 wire o2 sensor with a p05 ecu... or just disable it in the rom