1998 Civic CXi OBD1 Conversion Help?

[oatie]

Hi,
I've tried to do as much research as I possibly can before posting this but I
still do not fully understand.
I'm wanting to convert my 98' civic cxi to obd1 but the current ecu only has 2
plugs going to it, meaning obviously I can't use a conversion harness.
Now I believe what I have to do is hardwire the 3 plugs from an obd1 loom onto
my existing loomg using pinouts, get an obd1 dizzy or conversion harness for the
current dizzy, but I don't understand what I have to do for the injectors? Apparently
I need to add more wires for the Injectors? If someone could help shed some light
that would be great.
Thanks.

[ECU-MAN]

start by getting an OBDI schematic, that will give you an idea of what is needed.


P2K ECU banks two injectors together


When you convert to OBD1 you must separate the banking and wire each injector back to the ECU OBD1 A connector. Two wires in total to separate the injectors.


For the dizzy your best bet would be to get an D15B7 engine loom, unsheathe it and carefully pull out the dizzy wiring from the connector back to the shock tower plug. The fit it to your harness all the way back to the ECU. Ensure you maintain the shielding and ensure you ground the shielding at the ECU end only.


You also have to ensure everything else is wired up correctly.

[oatie]

Ah, that makes more sense..
So will I be needing to purchase new injectors to add new wires or that will be easily done with standard injectors?

The reason behind all this is to be able to run hondata on an obd1 ecu, I know I'd be better off doing an engine swap
of some sort in terms of making more power but I'm wanting to learn to tune and I figured this is going to be the cheapest
way I can learn if I damage anything.

thanks for the reply ECU-MAN! :)

[ECU-MAN]

Use your existing injectors and connectors


You will have to swap out the 3 wire IACV to the 2 wire IACV as well, the OBDI ECU cannot control the 3 wire IACV.

[oatie]

Oh boy, I've got some work ahead of myself >_>

Thanks again ECU-MAN
Why couldn't they have just used OBDI in Aus D:

[ECU-MAN]

Why couldn't they have just used OBDI in Aus D:


Because it became obsolete.

[oatie]

Well you know what I mean, how about just straight up OBDII.. easy >_<
you sound mad o_O

[SHOGUNOVDDRK]

you sound mad o_O
There is no sound or tone on the Internet m8o.

Good luck with the project OP and cheers ECU-MAN

[oatie]

There is no sound or tone on the Internet m8o.

Good luck with the project OP and cheers ECU-MAN

.... I'm just going to stop talking and stay in this hole i've dug myself here

[ECU-MAN]

you sound mad o_O


Not at all man

OBDIIa like the D16Y8 would have been better however the CXi is the base model and no doubt they would have wanted to build it as cheap as possible, so an ECU with a FAX machine CPU seemed logical.

For what the CXi is and what is has to do, it does it well. The PGMFI system on the CXi is unique amongst all other PGMFI systems.

[oatie]

hmm ok so..
by the sounds of things I'd be better off selling and starting off with a better base, something that can be chipped
straight off the bat, or converted simply by using a conversion harness..
Would I be correct?

[ECU-MAN]

That's up to you. Weigh up the costs and determine the best way around it.

[oatie]

Right so if I were to sell and start again, what are my options?
Were these civics the only cars in Aus to get this type of setup or are there other models that got the same sort of thing?
I'm having trouble finding that information.. for example the GLi, same engine.. but same ecu?

[Vvvtec]

why WOULDNT you just use a conversion harness if it's an option?

[ECU-MAN]

CXi and GLi, both the non VTEC variants of the EK use the D16Y4 with the P2K ECU so stay away from those if that's the direction you want to take.


A D16Y8 engine loom and conversion harness would be ideal if you can source them for what you want to do to your D16Y4, or make a custom loom.


End of the day you have to pay if you want to play.

[oatie]

I think I'll just go through with it as it is not my daily, more just a "cheap" little project for myself.
So I can take my time in getting things right, thanks again ECU-MAN.

[ECU-MAN]

dr1ftaX you wont get flamed, you don't have to delete your post dude.

[grifty]

why WOULDNT you just use a conversion harness if it's an option?

because that's not an option

[dr1ftaX]

dr1ftaX you wont get flamed, you don't have to delete your post dude.

Haha my bad, i just realised I answered my own question. OP is still trying to use stock ecu whilst trying to convert to OBD1, wouldn't the best option be to use a P28 ecu which is already OBD1?

[ECU-MAN]

OP wants to make a P28 fit the CXi


to do that the PGMFI loom needs to be "customised"


CXi is not OBDI nor is it OBDIIa (ECU connectors). It runs an optical distributor or CKP, TDC signal, 3 wire IACV and batch injection. So its not a Plug and Play MF


These items need to be altered in the wiring as well as installed to the D16Y4

[dorikin]

What he said ^

Fun fact:
Did you know EK1 P2K uses 2 out of the 3 OBD1 connectors. Honda must have had a tonne of these left over, more cost savings...

[ECU-MAN]

What he said ^

Fun fact:
Did you know EK1 P2K uses 2 out of the 3 OBD1 connectors. Honda must have had a tonne of these left over, more cost savings...


Factoid #2
Did you know Toyota uses those two connectors as well !, they are also used on the Honda ABS ECU's and are Orange in colour


Bare in mind the 2 P2K connectors are not directly wired to the OBDI format

[matt-g]

Hi ecu- man
I've read about immobilized removal thing in another topic I can't find it now but I need your help plz
I removed the immoblizer middle from the top of the ecu but my car still not crank or anything else
What should I do?
Thanks

[ECU-MAN]

You cannot just remove the IMMO PCB from the ECU, you need to install a bypass module to allow the ECU to work correctly. If the engine starts without the IMMO pcb the engine light stays on and the ECU may be in LIMP mode

You have to also bypass the starter cut relay

[matt-g]

Thanks so much for replying
How can I get bypass module and how much?

[ECU-MAN]

You should PM me about it.