Okay, quick question...I did do some searching about this and couldn't find anything.

I recently swapped in a 97-spec JDM ITR engine into my 96 Integra sedan and originally was using a P73-013 ECU (before I realized that it was a 98/99-spec ECU). Aside from throwing a code for a fuel tank pressure sensor (which to my knowledge only existed on 98+ Integras), VTEC engaged at ~4500 and fuel cut was at around 8200...I knew this was pretty weird because I thought VTEC and fuel cut were supposed to be higher than that (5700 and 8600? respectively).

Earlier this week I swapped in a P73-003 (96/97-spec, correct?), now VTEC engages where I originally thought it was supposed to, at ~5700rpm, and I have taken it to 8500rpm without seeing fuel cut (I'm still getting used to this whole revving high thing...I'm used to shifting at like 6700 with my old LS motor...).

I was not aware that there would be any differences between the 003 and 013, as I didn't think they made any changes to the JDM engines in that time (please correct me if I'm wrong). I popped open the 013 ECU and everything looked mint and untouched.

Can anyone shed some light on this or just tell me something I'm missing here?

In case it matters:
- misc short ram (good filter though), header, high flow cat, cat-back, fidanza flywheel
- oem IM, TB, fuel system (everything), internals (everything), pulleys
- of course still OBDII and all

Thanks,
--Brian

 

I found out the hard way as well....

P73-A03 is the USDM 97 and 98 ITR ecu (OBD2a)
P73-003 is the 98 spec JDM ITR ECU (OBD2a)
P73-A04 is 00-01 USDM ITR ECU (OBD2b with immobilizer)

The JDM P73-003 should run fine, but it's map is slightly different from what I have found out. Also, the JDM ecu does not have all the sensors that the USDM ecu has such as knock, and the vtec pressure sensor (possibly ELD as well as others).

Hope this helps

 

it sounds more like you have a P72-013. (GSR)

here's what the P73's came on/in
https://honda-tech.com/zerothread?id=2067011

for a 97 spec engine the P73-A02 would be the best bet (or a P73-003)

different cam profiles in the 96-97 models cause different fuel/ign maps. But it's a slight difference.

also a $1.29 radioshack part will get rid of the FTP CEL.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by MOVE OVER &raquo;</TD></TR><TR><TD CLASS="quote">I found out the hard way as well....

P73-A03 is the USDM 97 and 98 ITR ecu (OBD2a)
P73-003 is the 98 spec JDM ITR ECU (OBD2a)
P73-A04 is 00-01 USDM ITR ECU (OBD2b with immobilizer)

The JDM P73-003 should run fine, but it's map is slightly different from what I have found out. Also, the JDM ecu does not have all the sensors that the USDM ecu has such as knock, and the vtec pressure sensor (possibly ELD as well as others).

Hope this helps</TD></TR></TABLE>yep

 

After running the P73-003 for a couple of days now, and actually seeing how it reacts at WOT compared to the 013, the 003 seems to have less low-end power and a much more linear power band overall after say 3000rpm or 3500rpm, but still responds to throttle input and modulation just as well. The 013 seemed to have more low-end power, but it seemed as though VTEC kicking in at 4500 didn't allow the powerband to build as smoothly, and there was a noticeable power increase after 6k rpm.

So I guess I'll have to decide whether I want more low-end power for everyday driving (013) or a more linear powerband (003).

Also, my 003 is intermittently throwing a CEL for the knock sensor...I'll have to check that pin on the ECU connector first before worrying about anything else. The only code the 013 threw was for the FTPS

Could it be that my 013 ECU is in fact a re-stickered P72? If so, what could I do to compare the 003 and 013 ECUs or to otherwise check the 013 to see if it is in fact a P73?

Thanks for the info and input so far guys.


Modified by KaBlookie at 11:11 AM 9/9/2007

 

that description makes me think it's P72 even more. All though I've never run a 003 so maybe I'm wrong and that's simple the way the ECU works.

To check the true nature of your ECU, pull the top cover and read the three digit numerical code printed on the top of MCU (largets chip inside)
That code can be traced back to the original ECU number.

also there is a sticker on the connector that usually doesn't get swapped if the ECU is in fact a re-stickered or case swapped ECU.

 

I opened up the 013 ECU (003 is in my car, so I'll take a look at that one later), and here's what's on the MCU:

M66507 - 712 (big)
9092201 - BG2

I'm not seeing a sticker on the connector itself, but it does have "90353 1" engraved on it.

You're right though, it does almost seem as though the 013 is just a P72, because of where VTEC comes in and where the redline is...weird...

 

that's what I was afraid of... the 712 MCU code is the USDM P72.

713 = P73-013 & P73-023
I'm not sure what the 003 is.


here is the PGMFI.org page that has the MCU codes on it (I copied to my site for reference due to that part of their site being down) it shows what the MCU codes are and where they come from.
http://www.b18c5eg.com/EcuDefinitionCodes/

 

that blows...now I have to try to sell an OBD2a P72 in a P73-badged case...oh well

The ECU I'm running right now (P73-003) I'm like 95% sure is a proper P73, because of the VTEC engagement point and redline, although I'll check the MCU number just to be sure (should be 359).

Thanks a ton for the link and info guys.

 

Wow! little that i knew! sensei.

 

Im bringing post back to life cause I have the same issue but mine is in a 95 LS and 96-97 JDM ITR swap. I am running a P73-003 and it pulls decently but I dont hear or feel VTEC engagement. I troubleshooted it and all I came up with is there is no VTEC pressure switch on my VTEC solenoid. So my question is on 96-97 ITRs and the 003 ecu does it need a VTM switch to engage vtec. I had a b16 hatch and it seems that it pulled harder through the powerband. Thanks.

 

here man follow this link it will probably help you, i am using a p73-003 on my ls-vtec with a p72 gsr swap (not sure if it was a jdm or not)

anyways i followed this up and it did the trick for me:
MAKE SURE THAT YOU HAVE YOUR CAR OFF FOR STEP THREE OR YOU MIGHT RISK DAMAGING YOUR ENGINE, AND WHEN (OR IF) YOU DO THE ON THE ROAD TEST MAKE SURE THAT YOU ARE PAST THE 4500 RPM MARK OR YOU MIGHT DAMAGE THE CAR (I DO NOT KNOW IF IT WILL DAMAGE THE CAR FOR REAL BUT MY GUESS IS THAT, SINCE WHAT VTEC DOES IS LENGTHEN THE TIME THAT THE VALVE STAYS OPEN YOU MIGHT RISK A NASTY BACKFIRE)
http://www.d-series.org/forums/gener...-will-hep.html

all credit to the original poster

 

not quite

p73-a02 is the 97 itr and a03 is the 98, 98 had the fuel tank sensor which is the difference.

no idea what changed between p73-003 and p73-023, the motors are all more or less the same. in the US a02, a03 and a04 have the tank pressure and immobilizer coming on. to tell if there is any difference in the maps you would have to load them on a rom editor and look . i have never met a tuner that's actually looked at all the ecu's to see if any fuel or timing changes took place.

 

Try the hybrid forum--that's what it is there for. This entire post should be there, to be honest.

 

it's a dead worthless forum, no one posts there

 

If your car is ls integra you dnt have knock sensor, you need to run the one wire
for vtec to the ecu also jdm ecu don't read the pressure for vtec

 

I have a P73-003 do you know if this ecu supports ac as I am having trouble getting it to work.