ECU help

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New Member
Hi, all. Hear is my story. I paid a mechanic to swap the engine in my 98 honda civic ex (auto tranny). I didn't really know much about engine swap or what engine i had, before i read, a whole bunch of info about it on this site. (GREAT SITE!) The mechanic said it will cause me 2 G for the complete work. Which i was told by many that i talk to, was a reasonable price. He said he can get a low mileage engine for me also, which sounds great. Anyways,,,making the story short. i now got my car back and i have check engine light on and a flashing green light on the the "D" while i drive the car. it drives good but i need those lights out for emession. He said it will cost me another 500 dollar to fix the problem. He said he would have to replace 3 sensor (Example knock sensor) and i paid him that and i still have the same problem. i he said i dont know what the problem is...and he cant really help me. So i google for error code and green light problem and found enormouse amount of info. and I feel like i have been rob too. I found out that. i now have a D16Y5 engine in my car instead of the original Vtech D16Y8 engine. At this point after reading all kinds of info. I believe i need an ECU to solve my problem. So i bought an ECU with the # 37520-P2N-A61 which it didnt work cuz i have i have plugs for the "B" connection on the ECU and the P2N that i bought do NOT have any "B" connection. According to this site the "B" connection is for CIVICs with A/T and i have no idea what A/T stand for. When i plug in the p2n -a61 ECU, it starts but will not let me shift from "P" to any gears. so i put it in "N" and start it and it will shift buy will not go. So my question is, what ECU do i need (P2N what?)? Or can I rewire something? Please help!


New Member
sounds like you got raped big time by a unqualified mechanic who doesn't know jack about engine swaps...!!!


New Member
Where do you live?

I'd hate to say it, but I think the best thing you could do would be to find someone who knows their Honda's inside and out, and to have them do the work. And also, installing the same engine is always the safest bet.

It will save you time and money in the long run, trust me on this, I am presently learning the hard way after my engine swap has almost cost me $3500 (D17-D17 Vtec), when it was originally supposed to cost $1200. Not to mention it still runs like shit, air/fuel is all over the place, and doesn't even start half the time.

Good luck with your venture.


well lets see where to start..

You original motor was a d16y8 which is vtec, the new d16y5 that you now have is not vtec.
the a/t that you didnt know what it ment, means auto transmission
the p2n is the correct ecu for the y5 however you have a manual obd2b ecu you need a 37520-P2N-A51 which is obd2a

the plug configuration was changed between obd2a (96-98) and obd2b (99-00)
the last 3 numbers are what your looking at
a- american
5- automatic ecu, manual it will -1
1- software verson


Green on the scene.
yeah, sounds like he fucked you over big time.
next time, try acting like you know your shit, but you just dont have the time.