ECU P13 3GA and 3NO question

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ECU P13 3GA and 3NO question

Post by Ezomatsu »

I have an P13 3GA ecu coming from a european prelude (h22a4) and a P13 3NO ecu coming from a japansese prelude (H22A).
I know that there is a difference in the camshafts and in the pistons between a H22A and a H22A4, but I like to know if there is also a difference between the ecu's from these cars...?
The one has a knock sensor, and the other doesnt, I know, but something more?



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Re: ECU P13 3GA and 3NO question

Post by spiffyguido »

That's a tough one. Most of the label decoders out there are for civics, so it took me some time to get a vague idea of what those digits mean.

It seems that the ECU codes usually indicate three things:
-The market the ECU is for
-The type of board used
-Whether or not the ECU is for an automatic car or a manual transmission car.

I'm not positive about this, but I believe the 'G' and the 'N' indicate the market that the ECU is for. G is for EDM and N is for a non-specific market (i.e. it's a plain factory ECU).

I'm not sure what the 3 represents, but it might represent the type of board.

That leaves the last digit. Typically a 0 is used to represent a Manual transmission and a 5 is used to represent an automatic, at least for civic ECUs. Is that a 0 in 3NO or an O?

For your purposes, the most important thing to watch for will be getting an ECU that will work with your transmission. You can't run an ECU meant for an automatic in a manual transmission car. Other differences might come from whether or not the car had ABS or not.

I know that's not much help, but that's the little bit that I was able to find after hunting around for a while.

Are there ECU decoders in the manual?