I have a 1996 Honda Integra Type R. It is OBDI. I need it to be able to hook up to an OBDII scan tool and pass an inspection.

I know I can get an OBDII ECU, wire harness, dizzy, etc... but I need it to have a working OBDII plug.

Is this possible? How can I go about doing this?

Thanks

 

Nothing to add, but I hope you get your answer so I can get mine.

I'm in the same boat - 98 Civic with an OBD1 swap. Car's been off the road for years now, and I've been dragging my feet on even working on it. Very discouraging that even if I do get the engine put back together and running, I won't be able to drive the damn thing because it won't pass inspection. And now, in the great state of New York, if you don't get it inspected, you can't register it, either.

 

You're not going to get an OBDI ECU to talk to an OBDII scantool, which means you need an OBDII ECU. The OBDII plug that the scantool hooks to only has 3-4 wires going to it (despite the connector having 20+ pins), so it'll be easy to hook up.

 

You know, I've given that very thing much thought - installing a "parallel" ECU system hooked up to the OBD port in the car.

It would involve a **** ton of wiring, but if you could power up an OBD2 ECU, and feed it with signals coming from the various sensors in the vehicle (which are also connected to the OBD1 ECU running the engine), in theory, that OBD2 ECU should report "ready" to the DMV's scan computer.

A problem I could see with this would be that by tapping into the various sensor circuits, this could create a voltage drop that's outside the acceptable range that the ECU needs to see on that pin or pins, which would throw a CEL.

Which is why I thought about finding an un-modded car, and measuring all of the voltages outputted by the various sensors. One could then, again, in theory, build a "distribution panel" of a whole crapload of variable resistors. By feeding 12v into the panel, and adjusting the output of each pot, you could "simulate" the correct sensor voltage and connect each to the OBD2 ECU. Doing this might satisfactorily replicate a running OBD2 engine. However, if the OBD2 ECU needs to see a fluctuating signal of some sort, then the plan is blown to hell, and we start from scratch.

 

Yep I am in NY with an unregistered car now.

I have no problem converting the whole car to OBDII. ECU, distributor, conversion wire harness, the whole 9. The thing is even after you convert a car to OBDII from OBDI you do not have an OBDII plug. I am wondering how I can get a working OBDII plug in the car?

 

To be clear I am looking for a way to make a 1996 JDM B18C OBDI car hook up, scan, and pass emissions with an OBDII port. Willing to change whatever parts are needed to get it to work.

Is it possible to just wire in a OBDII plug into the existing wires in an OBDI car?

 

No, the OBD1 ECU obviously doesn't support OBD2 protocols. You need an OBD2 ECU, additional sensors needed for OBD2, and the OBD2 port itself wired up properly.

 

Hook a brotha up with some info on this! Who made it? PM me! LOL!!!


Might just need to do this even on a temporary basis so I can finally use that OG Tunerview I bought back in January of '08!!! LOL!!!

 

Yup. At least to pass.

 

You keep saying "working OBDII plug" as if the plug itself has any sort of electronics in it. It's just a connector...one that you can source from a junkyard car. The ECU connects to this connector through 1 wire (there is also +12v and Ground wired to this connector to power the scantool). This 1 wire is a data stream containing ALL the sensor values and more that the scantool decodes. It's not as if individual sensors are wired to this connector and the scantool is reading their values that way.

 

You're going to have to pick up a helms manual and start looking at wiring diagrams. there are only a few wires that go to the DLC iirc. Other than thats its just install OBD2 ECU, add secondary O2 sensor, perform CKF trick etc. Btw, try to get an early OBD2 P72, iirc the '96s, maybe '97s don't look for a fuel tank pressure sensor, later ones do and your car doesn't have one.

 

I am looking for what exactly I would need. I understand things will have to be changed.

When they were available they sold for $600+. The website is in the picture properties if interested.

I mean working OBDII plug so if it was plugged into an OBDII scantool or emissions center they would think it is an OBDII car and I could pass. You're telling me the plug has just a 12v, ground and one wire? I assume that one wire is the one that sends all the data from the ECU about the car allowing it to pass. Where is this wire tapped into exactly?

Ok thanks for the info.

 

Ok here is where I am at now. Please let me know what exactly is needed.

OBDII Plug wired correctly (Any info on how this gets wired? Where is the wire coming from? What do I tap into in an OBDI car to get the same signals as an OBDII car? I am afraid that even with an OBDI car converted to OBDII the plug will not scan correctly and pass emissions because of differences in chassis harnesses and other things.)

OBDII ECU (Does it matter OBDIIa or OBDIIb?)

OBDI to OBDII wiring conversion harness for ecu.

Secondary 4-wire O2 sensor. (I have heard this is only for US Spec. I have a JDM motor. If I get a JDM ecu do I still need this? To pass must I get a USDM ECU?)

CKF (Crank Fluctuatioin Sensor) Trick

Do I also need to get an OBDII distributor and conversion harness for the dizzy?

 

A 96 ITR is OBD2A from the factory.

 

I didn't catch the year of the car when I first read this thread....

If it's a 96, and has the original engine, you don't need to be worrying about any of this? Unless someone converted it to OBD1 to facilitate easier tuning?

But in addition to your list, you'll need to change the injectors (or at least the clips) if they're OBD1...

 

The car is a 1996 HONDA Integra Type R. It is right hand drive from Japan. Japan was still using OBDI in 1996.

 

No, ALL ITRs are OBD2 and use a P73 ECU.

 

Ok I looked into it and for clarification it looks like the JDM P73 has OBDII style plugs but does not have the additional sensors (like secondary o2, crank fluctuatioin sensor, etc) that an OBDII car would have. Apparently it is somewhat in between the two. Not sure of the difference between JDM and USDM P73's.

This leads to even more questions.

Would it still pass emissions missing those sensors even though there are no check engine lights or will it specifically look for those sensors?

Can a JDM ECU "connect" to US scan tools and emission centers?

The car does not have an OBDII plug under the dash to hook a scanner up to as it appears to be between the 2 systems. Hopefully the OBDII plug can just be wired in and make life easier but I dont know.

 

Its OBD2, sorta. JDM OBD2 ECUs use mostly OBD2A plugs and an OBD2 square style eprom. But they don't look for the extra emissions sensors as you stated and have no DLC, even if you wire up the DLC it still wont communicate with a scan tool, you have to run a USDM OBD2A ECU and add the extra sensors (in the case of the CKF its easier and cheaper to just fool the ECU with the CKF trick.)

 

Ok so if I get a USDM OBDII ECU (P73 right?) and the additional sensors would it be possible to wire up the DLC and get it to work or would the DLC never be able to communicate? That is my main question.

If it can be done I will need a USDM 1997 P73 (1997 so it doesn't have the gas tank pressure sensor).

If the DLC can be wired up then I will pick up the USDM ECU but then I need to figure out all the sensor differences between USDM and JDM. So far I believe the oil pump crank fluctuation sensor and pully, secondary 02, EGR valve, VTEC pressure switch, knock sensor and coolant switch are all different in JDM engines. True?

 

Yes.

Yes.

Some of thats true, some isn't. JDM engines have knock sensors the same a US engine, ITR engines don't have an EGR valve US or JDM. Coolant temperature switch is the same. You will need to add the purge solenoid, secondary O2 sensor, CKF (or do the CKF trick) vtec pressure switch (or tap the vtec pressure switch signal wire into the vtec solenoid wire) and finally add the fuel tank pressure sensor if you use an ECU that looks for one.

 

Ok very helpful thanks. Of course it leads to more questions...

1. Do you happen to know how to wire up the DLC. What exactly I should be tapping into?

2. Looks like it seems...

EGR valve (not necessary)
knock sensor (not necessary)
coolant switch (not necessary)
fuel tank pressure sensor for 98+ecu (not necessary for 97 ECU so Ill get a 97 ECU)

purge solenoid (no clue about this)
secondary 02
oil pump crank fluctuation sensor and pully (CFK Trick)
VTEC pressure switch (tap the vtec pressure switch signal wire into the vtec solenoid wire)

Doesnt seems too bad. Looks like I am almost ready to give it a go. Now...

3. How can I tell a 97 P73 from a 98+? Something in the serial numbers or anything?

4. If all this gets done will the car run like crap? It is a stock engine and I just want it to run stock.

Thanks again.

 

You'll be running wires back to the ECU IIRC, never actually done one but i seem to remember seeing a thread on it once before.

its not that bad, none of it is particularly hard, just takes some time to do.

The last digit will tell you, ECU number will be 37820-P73-A0X where X will be the revision, now i just have to find out what the revision for a '97 ECU is.

It will run exactly like a stock ITR.

 

ok i havent read everything they told u about how to convert OBD1 to ODB2

ok first of all... all the USDM car from 1996 and up are ODB2 it was required by law for all us car to be obd2 so the reason why your 1996 JDM type r is not OBD 2 is because it is a JDM ECU and they dont have a OBD (On board diagnostics) so in really its not even an OBD1 as u think it was... so since the us never made a 96 type r you cant just get all that stuff and convert it so the next best thing is to get it for a 97 USDM type r. so your going to need the OBD2A ECU and engine and chassis complete hardness. also the gsr should work but not going to give u full performance. if u get any 98 and up your going to be working with an OBD2B ECU. so to save u problem look for 97

 

Wow. You just posted in a 3 month old thread to add absolutely nothing new or useful, and to top it all off half of you info is wrong. OBD1 JDM ECUs are every bit as OBD1 as US OBD1 ECUs. JDM ECUs are different, yes. But to say they're not OBD anything is absurd. Also, OBD2B didn't start until '99 in Civics and '00 in Integras.