Non OBD to OBD1 conversion (By: Gold EF)

[Blue Hybrid]

Hi, there are alot of these charts floating around, but i found they are all wrong. I sat down and figured it out with a friend, made my own harness, and it all works fine. edit: let me check my harness again, then ill repost Non OBD-OBD1 conversion PR3 P30 A01 A01 A02 A23 A03 A03 A04 A24 A05 A05 A06 OPEN (A20?) A07 A02 A08 A04 A09 OPEN A10 A20 A11 A09 A12 A07 A13 A25 A14 A07 A15 B1 A16 A26 A17 OPEN A18 B2 B01 D01 B02 OPEN B03 A15 B04 A12 B05 D06 B06 A13 B07 OPEN B08 B05 B09 OPEN B10 B11 B11 OPEN B12 B12 B13 B09 B14 A16 B15 A21 B16 B10 B17 A21 B18 OPEN B19 D03 B20 D04 C01 B15 C02 B16 C03 B13 C04 B14 C05 D15 C06 D13 C07 D11 C08 D14 C09 B08? C10 D02 C11 D17 C12 D22 C13 D20 C14 D21 C15 D19 C16 D14 Modified by gold EF at 12:42 AM 2/5/2006 Modified by gold EF at 12:46 AM 2/5/2006 Modified by gold EF at 12:46 AM 2/5/2006

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[HondaPartsHero]

While we are on topic can someone confirm this diagram for OBD0-OBD1 dizzy. The plugs in the pic are as you were looking at the backside where the wires come out as if you were making a conversion plug.

[HondaPartsHero]

hello, mcfly?

[VtecSyndrome]

"McFly" has left the building...ha ha. you know I have this harness already and you live down the street from me? I could solve this real quick for you but i'm not going outside now since it's 2:18am, hit me up man.

[143MYVTECEF]

So if you repin your connectors you can run a OBD-1 ecu on a OBD 0 car?? Sorry new to this...

[HondaPartsHero]

Doh! I keep forgetting that, well PM me your number so we can get up like real soon.

[VtecSyndrome]

pmd

[Blue Hybrid]

Originally Posted by 143MYVTECEF

So if you repin your connectors you can run a OBD-1 ecu on a OBD 0 car?? Sorry new to this...

no, you have to make a jumper harness, basically you have to cut the male harness off a obd1 car from the junkyard, and unsolder the female harness part from an older obd0 computer, then match the jumpers to the chart, and you can now plug in the obd1 computer to your obd0 harness

[VtecSyndrome]

Originally Posted by gold EF

unsolder the female harness part from an older obd0 computer

yeah, that part was real fun considering I did not have the right tools for smooth removal

[Blue Hybrid]

Originally Posted by VtecSyndrome

yeah, that part was real fun considering I did not have the right tools for smooth removal

i used a butane torch, took about 10 seconds each

[143MYVTECEF]

What are the benifits of running a OBD1 computer on a OBD0 Car?

[Blue Hybrid]

depends on wich obd1 ecu you use, the most popular one is the p28

it has the least amount of sensors and has vtec. obd1 computers are far faster at calculating air fuel ratio than obd0, obd2 cannot be easily modified, thus obd1 is the best choice. just by upgrading to obd1, an engine can gain 10 hp

[CR-V-tech]

hey gold ef I have an 88 hatch dx, I had the engine harness converted to obd1 mpfi by hasport, then I bought a boomslang obdo to obd1 jumper harness, and now nothing is pinned the same the engine harness wires don't match the harness that goes into the car and when I call hasport they say that boomslang's harness is pinned differently than the way that they do so then I call booomslang they tell me that all I have to do is repin 4 wires that go to the dizzy ckpp, ckpg, cypp, and cypg. this is just a big f-ing hassle and is really starting to piss me off. do u have any ideas, I already repinned the 4 wires like they said and still no spark! I just want to burn the car to the ground, fuel pump doesnt come on and i have no spark, and also my injectors aren't firing either. the car cranks and almost all of the other electronics work. I am so f-ing confused. Oh and I also tried to use the factory wiring diagrams and that doesnt help at all, the obd0 ecu connectors are pinned for a dx, but the engine is mpfi and obd1, I mean i'm a fairly skilled individual but if these companies are goin to make this shit u would think that they would all try to be on the same page! hit me back man please

[vtecn8ive]

I am going to have to so DON'T use this conversion harness pinout. Did you see how many repeats you have. You are seriously using this? Does the car run?

Curious why you used a pr3 (which is already for vtec JDM) and pinned it out against a p30 (which is vtec JDM too)?

Most of us use pm6 pinouts a lot more common.

here is a link I have used multiple times. In fact I was one of the first guys on that thread to make mine. Still going strong too.

http://www.honda-tech.com/zero...age=1


Sorry not trying to rip on you but I think some of your pinouts need to be double checked.

-Shane

[VtecSyndrome]

Originally Posted by CR-V-tech

hey gold ef I have an 88 hatch dx, I had the engine harness converted to obd1 mpfi by hasport, then I bought a boomslang obdo to obd1 jumper harness, and now nothing is pinned the same the engine harness wires don't match the harness that goes into the car and when I call hasport they say that boomslang's harness is pinned differently than the way that they do so then I call booomslang they tell me that all I have to do is repin 4 wires that go to the dizzy ckpp, ckpg, cypp, and cypg. this is just a big f-ing hassle and is really starting to piss me off. do u have any ideas, I already repinned the 4 wires like they said and still no spark! I just want to burn the car to the ground, fuel pump doesnt come on and i have no spark, and also my injectors aren't firing either. the car cranks and almost all of the other electronics work. I am so f-ing confused. Oh and I also tried to use the factory wiring diagrams and that doesnt help at all, the obd0 ecu connectors are pinned for a dx, but the engine is mpfi and obd1, I mean i'm a fairly skilled individual but if these companies are goin to make this shit u would think that they would all try to be on the same page! hit me back man please

My budddy had the EXACT same problem and he swore up and down that everything was wired right. Well it was but the problem he had was B10 and B12 were not pushed in the right way, when he repinned them he had them upside down which in turn prevented them from making proper connection when the harness was plugged into the ECU. I repinned them correctly and it fired right up! and since it was his first time doing a wire job like that he did not think of that possibility. maybe your lucky enough to have this same problem.

Originally Posted by 143MYVTECEF

What are the benifits of running a OBD1 computer on a OBD0 Car?

I was used to OBD 1 Vtec because I had my motor in a '95 EG and a '92 GSR before the REX and when i first drove the rex I had it on OBD O that being the only difference between my other cars prior. It was slow as hell feeling and it bogged badly when Vtec engaged, it also had a speed limiter of 112 which I hit pretty quick. I learned about the diff between OBD 1 and converted using a JDM PR3 ECU from an XSi and a Rywire harness and DAMN it felt like my old motor again! I definetely felt like a 10hp gain or close to it so I now hate OBD 0, you can chip the OBD 0 ECu but why do that when it runs soo good off a stock ECU from OBD 1??? it was a no brainer for me.

[Blue Hybrid]

Originally Posted by vtecn8ive

I am going to have to so DON'T use this conversion harness pinout. Did you see how many repeats you have. You are seriously using this? Does the car run?

Curious why you used a pr3 (which is already for vtec JDM) and pinned it out against a p30 (which is vtec JDM too)?

Most of us use pm6 pinouts a lot more common.

here is a link I have used multiple times. In fact I was one of the first guys on that thread to make mine. Still going strong too.

http://www.honda-tech.com/zero...age=1


Sorry not trying to rip on you but I think some of your pinouts need to be double checked.

-Shane

do more research before you knock it

pm6 is usdm si, cross it with pr3 or pw0, b16a jdm, they are almost identical, then do the same with p28 and p30. both identical pinouts

the repeats are powers and grounds. the obd1 ecu requres more powers and grounds than the obd0 one, thats why you have to use some of them. and if you read the original post, i made this harness, exactly the way it is, and it works

so

[Blue Hybrid]

Originally Posted by CR-V-tech

hey gold ef I have an 88 hatch dx, I had the engine harness converted to obd1 mpfi by hasport, then I bought a boomslang obdo to obd1 jumper harness, and now nothing is pinned the same the engine harness wires don't match the harness that goes into the car and when I call hasport they say that boomslang's harness is pinned differently than the way that they do so then I call booomslang they tell me that all I have to do is repin 4 wires that go to the dizzy ckpp, ckpg, cypp, and cypg. this is just a big f-ing hassle and is really starting to piss me off. do u have any ideas, I already repinned the 4 wires like they said and still no spark! I just want to burn the car to the ground, fuel pump doesnt come on and i have no spark, and also my injectors aren't firing either. the car cranks and almost all of the other electronics work. I am so f-ing confused. Oh and I also tried to use the factory wiring diagrams and that doesnt help at all, the obd0 ecu connectors are pinned for a dx, but the engine is mpfi and obd1, I mean i'm a fairly skilled individual but if these companies are goin to make this shit u would think that they would all try to be on the same page! hit me back man please

i dont mean to be a smart ass, but id say either get a new harness, or go thru yours wire by wire

[VtecSyndrome]

Originally Posted by gold EF

i dont mean to be a smart ass, but id say either get a new harness, or go thru yours wire by wire

Could be right, I have not checked mine yet but in a week or so I will start going through it so I can make a replica since i already have what I need. As soon as I get my list together I will post it because it works for sure in my car!

[143MYVTECEF]

Ok sweet but what else is needed besides the ecu and jumper cables inorder to make this work proberly?? And whats that best ecu to run??

[K20EF8]

Originally Posted by HondaPartsHero

While we are on topic can someone confirm this diagram for OBD0-OBD1 dizzy. The plugs in the pic are as you were looking at the backside where the wires come out as if you were making a conversion plug.

That is correct, however I believe the plug is upside down

[HondaPartsHero]

I was looking at them like this

[CR-V-tech]

THE CAR IS STOCK, WITH AN LS MOTOR, hasport did the engine harness, then all i did was add the 4 wires at the ecu plugs, 2 for the dizzy, and 2 for the injectors, other than that the pin placement for the ecu is the stock dx wiring!!!!! but i had to pull two wires out to install 2 of the new ones and hasport just says to tape them up or heat shrink which i did, then i called boomslang they said that all i have to do is repin 4 wires and all is ok but that isn't right, cuz last night i was checkin the wires at the dizzy and the there are two orange and two white wires for the crank pos sensor,when there should only be 2 and the two that are wired in for the hasport conversion aren't even on the right pin locations for the two on the dizzy's connector ! oh and FYI, i am running an obd1 pr4 ecu hooked up to the boomslang jumper harness connected to the stock dx ecu plugs w/the exception of the four wires that i added for the hasport harness, and then the hasport converted obd1 engine harness! so if u have any valuable info i would appreciate it

[CR-V-tech]

bump

[VtecSyndrome]

You need to check to wiring anyway, that's all you messed w/ so that has to be the problem. I can't find my diagrams right now but I had this problem a few weeks ago, you need to be concerned with B10, B12 and also C1 and C3 (I think but can't remember the C section too well) the 2 wires you pull out of the Harness need to wire back into the dizzy, you will see what I mean if you look up the conversion diagram and really follow it closly..

My buddy wanted to burn his car to the ground becuase he was overconfident and swore the wires were good but in the same case all he messed with were wires so thathad to be his problem, we went through it again and found the problem, I now it sucks but that has to be where your problem is. Don't let it get you down too much becuase when you get it running you will most likely want to kick yourself due to how easy it ended up being.

[vtecn8ive]

Originally Posted by gold EF

do more research before you knock it

pm6 is usdm si, cross it with pr3 or pw0, b16a jdm, they are almost identical, then do the same with p28 and p30. both identical pinouts

the repeats are powers and grounds. the obd1 ecu requres more powers and grounds than the obd0 one, thats why you have to use some of them. and if you read the original post, i made this harness, exactly the way it is, and it works

so

As I stated pm6 is not the same as a pr3.

For example the shit that is wrong:

A04 needs to go to the engine bay for Vtec solenoid. This is where a subharness comes in play so you can convert to obd1 oxygen sensor, and vtec, knock.

B08 is for Powersteering. Why would you hook this up? I guess unless you are running this harness in a 90-91 Integra or have converted your CRX to power steering it will benefit you.

D03 is for Knock Sensor and you have it hooked up to the ELD (b19)? why?

D06 is for vtec oil pressure switch and you have it hooked up to B05 which is clearly not for it.

D14 is for the oxygen sensor and you have it hooked up to C08 which is EGR VLS. The EGR VLS pinout is D12 (for your info)


Oh yeah is your vtec working? Your not throwing a O2 Cel are you?

But good luck you guys. I'm off of this thread apparently there are like 3 different conversions going on in this thread that don't really relate to the Thread Topic.

Peace,
Shane