tonyxcom

Here is the deal. I have a 00-ITR swap that I want to put into my 96 CX. I am planning on getting the car legalized so I MUST use the 00-ITR ECU. The immobilizer is being taken out, so that is a non issue.

I have basically figured out that NO off the shelf honda engine harness will work for this particular setup. Any harness you use, will have to be heavily modified.

A little background info.

When a 96 Engine harness enters the cabin, there are 4 plugs that goto the ECU, and another that connects to the Main Cabin harness and another junction connector.

When a 99 SI engine harness enters the cabin, there are 2 plugs that goto the ECU, another to the Main Cabin harness and another to the junction connector. There is also a connector from the main cabin harness that goes into the ECU.

The 96 CX engine harness will NOT plug into the 00-ITR ECU.
The 99-00 SI engine harness will NOT correctly plug into the cabin harness' on my CX. AND ECM/PCM Connector A will be missing, since this comes from the cabin harness in an SI.

In order to make that mising plug, I initially thought that I could back trace wires in the cabin harness, and signals in the junction connector using the schematics in the helms. Needless to say, this is the long way to go about it.

I am now thinking that the easiest way to go about this is to get a 96-00 EX M/T harness (they are all the same - the 98-00 EX harness has 4 ECU plugs like my 96 CX).

Once I get that harness, I will then need the 3 ECU plugs that go into a 00-ITR ECU. Should not be hard and I can cut harnesses to get them.

Once I have the harness and ecu plugs, I will take the ECU plugs off of the EX harness and put the 00 ECU plugs onto it, using the Helms as a guide.

I have accounted for every wire on the ITR ECU on the EX ECU and their locations on the ECU harness, so putting the ITR ECU connectors on should be a no brainer.

NOW. Is there anyone that has actually performed this swap that can add some insight?

As far a making this swap legalized in CA, I have also found out one major problem. I need to replace my gas tank, since the 96 hatchbacks dont have the Fuel Tank Pressure Switch. In doing that, I will also have to get the newer charcol cannister and run two new hardlines from the tank to it.

Thanks for reading and your input is appreciated.


[Modified by tonyxcom, 12:37 AM 8/12/2002]

bikeboy80

All i have to say is DAMN!

sounds like what you are saying will work and i definatly agree, that cutting the least number of wires will be best

i know you have probally thought of it but one question, can you use the itr harness from the ecu up to the passenger front, and just rewire for the headlights? not sure on how it would plug into the main cabin harness, just a thought

HXMan

FYI. All 96-98 Harnesses are basicly the same, using same connectors and same wire patterns.

All 99-00 Harnesses (EXCEPT the HX with manual tranny) are different then the 96-98 Harnesses.

Just use a 96-98 EX harness. You will have to change around nearly ALL the wires at the ECU. About all honda did at the ECU in the 99+ models is change one of the plugs(eliminated the D plug in 99+ manual tranny cars), and move all the wires around. I thought about trying to use a 99 Si ecu with my swap, but I didn't want to go thru the hassle of moving all those wires, and putting in a different connector.

So you will need the 96-98 Ex harness, A, B, and C ECU plugs, the fuel tank from a car with a fuel pressure sensor, different evap can...and that is about it.

One thing I am not sure about is if the wires are already existing for the Fuel pressure sensor, or if you will have to add them.

OH, and don't forget about the secondary O2 sensor. EX harnesses only have the primary O2 sensor wires built into them. Ex's have the secondary O2 sensor wires built into the chassie harness.

Good luck man, let me know how the fuel tank goes. I got around the problems you are having by using a 96 GSR ECU. It is the only DOHC OBD2 ecu I could find that didn't look for a fuel tank pressure sensor. The wierd thing is I had another 96 GSR ECU, and it threw a DTC for the fuel tank pressure sensor.

97hb

I have the same problem. Code 91 . For the inspection, I just reset the ecu and the check engine light will stay off for a couple of days and then come back on. You need new gas tank, charcol canister with the purge built in, and if you use the ex harness it should already be wired up for the gas tank pressure sensor and charcol canister purge.

HXMan

Engine harness will not have the wires for the fuel tank pressure sensor. The sensor is in the tank itself.

tonyxcom

Thanks for the info guys.

I will look at the 96-98 vs 99-00 harness and wireing differences at depth soon.

One thing that I can see right off the bat is that I cannot find a wire on the 96-98 EX Ecu for "NEP (Engine Speed Pluse)" that is pin A-19 on my ITR ECU. But that pin exists in the 99-00 EX ECU.

Also, the distributor plugs are different between 96-98 and 99-00 but the 96-98 actually match the pinout of my ITR Dist, so that puts me in a better spot as well.

Again, thanks for the info. There isn't any published data on the web anywhere that I have found, so I am having to figure it out all myself.

97hb

Good luck man, hope it runs strong.

tonyxcom

97Hb - The Helms says that the PTANK Sensor pin on the ECU should read about 2.5 volts from the PTANK Sensor itself when the ignition is in the ON position.

My guess is that you can try taking a 12 volt source (only when ignition is in the ON position) and putting at least a 5watt reisistor of (? Ohms) to bring it down to about 2.5V and connecting that to the PTANK ECU Pin.

That should get rid of the code. I will try that myself, but I am at least a month away.

Give it a shot and let me know if it works.

kenji

Tony,

I can make you a plug and play ECU conversion harness to allow you to run the '00 ITR ECU (as long as the immobilizer is removed).

You are on the right track with the PTANK sensor. But, the voltage varies depending on pressure. Look at the Helms manual again and it gives a voltage vs. pressure graph. That is something that you may want to consider.

-kenji

tonyxcom

Kenji, thanks for the offer on the conversion harness, but I am going to be bringing my car to a CA smog ref and will get failed for that.

If you can sell me the plugs that go into an 00 ITR ecu you will keep me from ruining a perfectly good 99SI harness.

Let me know if you can sell them to me.

Jackson

Jeff Sloan put a 2000 itr motor into his eg and ran a 98 usdm itr ecu so he wouldnt have to deal with that 2000 ecu. He told the ref station the motor was a 98. I dont know if they would be able to tell the year of the motor and/or the ecu. I would suggest running the 98 jdm itr ecu. It plugs into your year harness and it wont give you that PITA code 91. Other than that, do it the hard way and run the 2000 ecu. But I am pretty sure if you remove the immoblizer, it will give you a cel, which will probably cause a problem as well when you try to Ref it.
Or...
Run the 99-00 si engine harness and the interior harness so it makes it more of a plug and play deal, so you wont have to mickey mouse the wiring.


[Modified by Jackson, 10:48 AM 8/12/2002]

tonyxcom

The ref can tell the year of the motor when he runs the VIN. I didn't know that having the immobilizer removed will throw a cel too, but I'll cross tha bridge when I come to it. Thanks for the info though.

I know that my ECU must match the motor, and that I will basically have to prove that this ECU belongs to this motor if he can't figure it out himself.

It would have been way easier for myself to get a 97-98 ITR motor, but when shopping for a USDM ITR motor, beggers cant be choosers

kenji

Tony,

Just sell me your '00 ITR swap and be done with it.

Seriously, what about using a '00-'01 JDM ITR ECU. Do you think the ref would know it is from a JDM car? I am not familiar with the CA smog refs.

-kenji

tonyxcom

I am not sure what the ref does to the ECU, but I am sure he will read it to see if it is throwing codes. And I would assume the JDM one will read a lot different.

It all comes down to the ref. Some will just do a really good visual then sniff your car, and others will do a full out **** type inspection of your car and anything that has to do with the motor.

So I have to prepare for the worst.

Kenji, I also sent you an email. Let me know what you think.

kenji

The JDM ECU will throw the same codes as the USDM ECU. However, the JDM ECU doesn't look for a CKF, secondary O2 sensor, nor a PTANK sensor.

The only visual difference between the JDM ITR ECUs and USDM ITR ECUs is the '0' instead of an 'A' in the last three letters/numbers in the part number sticker.

-kenji

Jackson

Tony,
I think the jdm itr ecu is your best bet. The plugs are the same as your 96-98 plugs. Just tell the ref guy you got the ecu with your motor.

tonyxcom

Jackson, thanks. One more option I will consider.

HXMan

A JDM ECU doesn't look for those sensors...wierd.

97hb

I need a JDM ecu baby.

kenji

The one bad thing about JDM ECUs is that they have a speed limiter and some have been shown to make less power than their USDM counterpart.

[sarcasm] I just don't understand how they make less power they are JDM y0! [/sarcasm]

-kenji

97hb

While on topic, does anyone know if this code "91" puts the ecu into some sort of safe mode, or limp mode??? The car still runs pretty strong, its just for a evap, or emmisions related. I still passed inspection so I am not worried about that . Also glad to know there are people out there who know about this, because when I first did the swap, everyone was clueless, including the dealer(they don't know ****).

tonyxcom

I was told by one of the owners of a shop around here, that the gas tank swap is pretty easy.

He said he can get the gastank and newer charcol canister for about 200-250. Then you just need to run a few wires to the tank for the sensors and run two hardlines to the canister.

I will probably end up doing it because I have changed everything else in the damn car already, why stop at the gas tank

However, I wont be doing that at the time of the swap. I will also look into a way of tricking the ECU to think the sensor is there, and use the gas level sensor to automatically vary the voltage

kenji

97hb,

You can get a '97 LS ECU and it does not look for the gas tank pressure sensor. The '98-up ECUs have that 'great' feature.

-kenji

97hb

Thanks dudes, I learn so much from my fellow H-T members

Trey

Another way to make the code 91 not come on is to "prime" your fuel pump before starting the car.

What I mean is turn the key to the second position but DO NOT crank the car. That will energize the pump. Once the lights one the cluster go off, start the car.

Works every time.