Like it says, does anyone know what type of ECU came in the '89 LXi (A20A3, 5sp)?
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Like it says, does anyone know what type of ECU came in the '89 LXi (A20A3, 5sp)?
Wow, nobody knows what type of ECU we have?
By type do you mean OBD 0 (a.k.a. "PRE OBD") or the part number for a '89 LXi (A20A3, 5sp)? 37820-PJO-AO3 is the number for an '89 to the best of my knowledge.
Thanks for the info. I meant, for instance, 88-91 civic/crx have a PM6, 88-89 1.6L integra have a PG7, etc. I'm assuming that mine is the PJ0?
Okay, I've been checking around on other boards, including Homemadeturbo.com, Honda-Tech, etc., and all seem to be in agreement that another Honda ECU could be used in our car. If it is one that is chippable for boost, then this would certainly solve the engine management issue. Darryl at Openloop Motorsports has already done an OBD0 to OBD1 conversion on his A20, using an Integra P75 ECU and a dizzy from a F-22 Honda Accord.
http://3geez.asmallorange.com/showthread.php?t=18160
I've spoken with Darryl, and he is not going to be able to be much help on this. Sounds like a pretty nice fellow, but he did not keep notes when he did his swap, and is too busy with work to be able to do a "how-to" writeup on it. He did say he would try to help with questions I may have as I try to do it myself though, so that might be one resource we can tap.
The OBD0 to OBD1 swap is very difficult though, as the wiring/sensors between the different era ECUs is quite different. From what I've gathered so far, just about all OBD1 ECUs share the same pinout, so if you have the pinout for say a OBD1 P72, it will be the same for a OBD1 P75. I happen to have one, but when comparing it to my OBD0 PJ0, it is quite different, and would take a lot of effort to make the harness necessary for the upgrade. Still, it has been done. The nice thing about the OBD1 swap though, is that any OBD1 ecu will plug in, and it also opens up the use of Uberdata for boost management.
Still, if this is too hard a chore, we can still use an OBD0 chippable ECU, such as the PM6 ('90-'91 CRX Si - OBD0) and others. I chose this as an example, because it is very popular, and a lot of modifications have been done to this type by other Honda enthusiasts.
I am still very much an amature at all this, but I'm learning as I go. Still, if you guys who are serious about boost think this is a viable path, and would like to get on board, drop a note and let me know. I have pinout charts for the A20A3, PM6 and P72 if you would like them.
For anyone reading this who can see any fatal errors in this, please be sure to speak up and save me/us some unnecessary grief.
Please share your thoughts on this.
Thanks,
Rob.
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Yeah, that seams to make sense, according to this info from http://hondata.com/techecuid.html
Quote:
The part number consists of three components:
Honda's part number for ECU, which is always 37820
Three characters (which are loosely related to the model of car/engine). e.g P72
Three characters (which are the revision of the ECU) e.g. A01
