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Discussion Starter #1
New here and have been reading everything on ECUs and tuning, but it hasn't helped. My searches have not shown me any specific answers: Is it safe/smart to run this JDM P5p-003 with the H22A4 ?

I bought the car w/o knowing the ECU was changed from the stock P5M-A52 to a JDM P5p-003. The engine is a Vtec H22A4, and I'm not sure about any modifications.

Of course it didn't pass Emissions, but I did get a 2 yr. waiver.

QUESTION: Is it safe/smart to run this JDM P5p-003 with the H22A4 ?

If yes, can anyone point me to an explanation or comparison of the two ECU?

What are the pros/cons in running a JDM S ECU on a Base H22A4 ?

Thanks 2 degrees in advance
 

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I'm not up on the ECU numbers but the JDM ECU that came with my H22A was OBDI and USDM motors are OBDII. There are a bunch of things I had to change over to make my JDM H22A work with OBDII emissions system- do a search to find out all. Makes me wonder if the H22A4 was retro fitted to work with JDM computer. Bunch of pain for you if it was. The change over was pretty easy with the motor out. In the car would be different.
Pretty easy to check- been five years so I'm a bit rusty but looking it up should make it a snap.
BTW- my H22A has no problems with the US ECU.
 

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Discussion Starter #3
I'm not up on the ECU numbers but the JDM ECU that came with my H22A was OBDI and USDM motors are OBDII. There are a bunch of things I had to change over to make my JDM H22A work with OBDII emissions system- do a search to find out all. Makes me wonder if the H22A4 was retro fitted to work with JDM computer. Bunch of pain for you if it was. The change over was pretty easy with the motor out. In the car would be different.
Pretty easy to check- been five years so I'm a bit rusty but looking it up should make it a snap.
BTW- my H22A has no problems with the US ECU.
Hey! Thanks for the reply. It doesn't look like the PO did any changes to the H22A4. I've posted this on a bunch of other boards (including Honda Tech) and have received no other replies. I've also done extensive google searches for ECU comparative data (programming and compatibilities) but have found few sources.

I'm thinking of taking it into a local tuner to get a reading on WTF is up with this combo. It runs really well, seems that VTEC engages around 3100 or so (a little low?)

I'm also thinking about buying the original ECU that should be in the car from HMotorsOnline, who actually have one of the OEM that's IMob bypassed like mine.
 

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There really is no benefit to running a jdm ecu, especially if you have to pass an emissions inspection. That will never pass. If you have all the right sensors to match with that ecu, it won't hurt anything.

The jdm and usdm h22 (and h23a) engines are all very similar, the only difference between them that will matter for the ECU is that some of the sensors are different. The crank position sensor and distributor are different, for example.

I used a conversion harness to run my jdm engine with a chipped p28 and the original USDM H22 electronics, everything was plug and play. I used a p28 because none of factory H22 ecu's can be reflashed for a tune. Best you can do with those is get a VAFC that lets you adjust the vtec engagement point.

If you need to pass emission, a p28 is also a no go. Your only option for that is to find a USDM H22 ECU, along with all the other USDM emissions stuff.
 

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Discussion Starter #5
Thanks. I need to check out the sensors and distributor to see if they were changed on my H22A4 to run the JDM ECU. Anybody have a clue why the PO would have made sensor and distro changes to run a JDM ECU?? I'm thinking of buying the stock ECU from one of the suppliers and swapping it out --if I can verify the sensors and emissions stuff are in place. Anybody have a checklist for de-modding this kind of mess? Thanks.
 

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Discussion Starter #6
SOLVED.. wrong ECU. Marked wrong. Changed out and now runs great.

Anybody need a p5p atts ECU cheap?? HMU.
 
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