I'm about to do an ITR swap in my 95 CX hatch. I was wondering if it was better getting a USDM ITR harness, Or just modify my CX harness? I heard that the USDM OBDII harness will plug into OBDI cars. I don't mind paying the extra $$ for the harness as long it's done right, clean and reliable. Anyone done a swap with a OBDII harness into a CX? I've seen VX but never CX.

 

IMO, the USDM harness is worth the money. practically plug and play, no rerouting of wires required. (00-01 harnesses require the tach wire from the distributor to the driver's shock tower to be added)

You'd have to add at 2-5 wires from the shock towers to the ECU. (depending on what ECU you use)

 

Let's say i'm going to use the 98+ JDM P73 ECU. Would it still work? Also Wouldn't I still have to add some wires like vtec cause the 94-95 EG didn't come pre-wired for vtec like the 92-93 did?

 

If your using the 98+ ecu; you'll need an ECU obd1-obd2a conversion harness; plus alot more wiring for the secondary O2 sensor; CKF sensor; and other sensors.

 

So I have to go out and buy a different ecu if I don't want to wire up all those things? What are my choices of ecu's and where could I get them. Located in So Cal

 

if you're in cali you'll need to set the car up so it passes smog. JDM Engines will not pass smog without some parts swapping. (do a search on here... this has been convered in super detail)
Also, JDM ECUs will never pass smog because they will not communicate with the typical code scanner.

special note: JDM ECUs do not need the secondary O2 or CKF sensor. (I run a JDM P73 in my OBD1 car with zero additional sensors in place)

 

so do you have a itr swap and running the jdm ecu? I'm not really worried about smog for now. So I have to get a chipped P28? There is no other way to run the jdm P73 without adding those sensors you were talking about. Also i think i'm leaning more towards the 98+ ITR swap.

 

the chipped P28 is not a bad move, all though IMO a chipped P30 is a better way to go. the additional wiring for the knock sensor may be a little bit of a pain but if you're planning on not tuning for a little while... the knock sensor can save you.

I have a '00 B18C5 (USDM ITR) running off of a JDM P73-023 (00-01 spec)
I ran a chipped P30 that I tuned myself for a long time, but had to revert to the "stock" ECU to keep competitive for autocross.

the 98+ is a good move, the earlier versions are good but the later ones have more goodies from the factory.


Unless you plan to register the car out of state I'd be thining about emissions now. It will hurt a lot if you can't get past them when you need to.

the USDM version of the ITR (B18C5) is about the same price and it will have all the parts needed to pass emissions in the future. Not to mention that the 00-01 version is basically identical to the JDM counterpart other than a slight bump in compression.

 

Yeah, I decided to go with the 98+ spec. When using the stock P73, the JDM ITR's doesn't have a CKF sensor. The only thing it would be looking for would be a second O2 sensor. right?

 

Typically... JDM ECUs = no secondary O2.

the FTPS needs a $1.29 radioshack part to prevent the CEL, but other than that it will work perfectly on your OBD1 car. (with an OBD1 to OBD2a conversion harness)

again, other than emissions/smog testing. (sorry to sound like a broken record on this point, but it's usually considered a major thing)

 

do your best not to cut harnesses. just turns out to be a mess