b18c7 obd2 into obd1

[ucme]

Hey guys
I've done a bit of research on the conversion but am still confused about a few thing. If i want to run the obd2 ecu with the obd1 loom and obd2 harness what do i need to do?

[Bludger]

I would like to know also.

Some one that has done this please share.

[89lude]

to run the stock ecu you need to buy an obd1 to obd2 conversion harness. jdmyard has it or 50 bucks.

as for the wiring on the engine harness/interior loom you have to rewire a few things, best to let someone who knows what they are doing do it.

[ucme]

What about if i change everything to obd2. Will it be as simple as plug and play?

[thaizeg]

To run the obd2a harness u will need to chop ur obd1 and obd2a( leave about 10cm of wiring at least connected to the obd2a plugs) where it plugs upto the ecu and rewire in the obd2a ecu plugs and wiring to ur obd1 wiring which is still on the car harness. You will need a pin out diagram for both ecus so u can match the wires together( as they may not be color matched). I had a mate do this to my car it took him a few hours to ensure all wires are correctly connected and then soldered together. Essentially ur car will now only run on obd2a ecus. To be able to run obd1 ecus again u will then need an obd2a-obd1 harness. If u want to run an obd1 ecu in future u will need an obd2a-obd1 harness which are about $50.

Alot of time and hassle if wires go wrong.

Recommended to just get an obd1-obd2a harness from the states for under $200. Saves u all that trouble.

[ucme]

Cheers for the info. But again does anyone know if i can just change everything to obd2 as i have the loom harness and ecu. Any info appreciated

[thaizeg]

U can but then again u will need redo the wiring for all the plugsnin ur dash... For ur cluster and heater etc to work.. This would be a good option if u were to do a dc2 dash conversion as yhe dash will be taken out.

[ucme]

Itd be much easier i presume re-wiring the dash plugs then the engine bay loom. Thanks for the info

[fatboyz39]

All you need is a conversion harness OBD1- OBD2a ECU

[thaizeg]

Still unsure why u wanna go through that trouble dude..
Whatever floats ur boat i guess good luck

[ucme]

i dont mind having to rewire stuff. i just see rewiring the ecu as more effort than the dash. im planning on using the dc2r cluster anyway so may be half the trouble. anyone with pinout diagrams on obdI and obdII ecu's?

[androoz]

As thai and fatboy has said, re-wiring the entire dash loom is not necessary. Even if you want to run the dc2r cluster, you will be creating more trouble than its worth.. Your fan/ac switches may not plug back into the dc2 harness etc etc..

There are two ways to make the OBD1 car run the OBD2a ECU and motor;

The easy way: Buy the harness.. plug and play (after running a few extra wires from the engine loom/strut loom to the harness/ECU)

The other way: Re-wire the OBD1 car ecu loom to OBD2a (This was how most people did it years ago when the harness were not as readily available as they are today, takes hours to do it properly, but looks much neater when done right).

Your way: UNNECESSARY.. You may get the motor and dc2r cluster running, but what about everything else?

You asked for simple plug and play, but when told of the answer for plug and play you dont want to do it?