I dont know if there is a law about what you are specifically trying to accomplish,but there is a general, more broader Federal law regarding tampering with anything related to emissions. The PCM and its associate parts are tops on that list.

Interesting concept. I think youll find engineering a communications protocol to work a bit challenging(unless youre knowledgeable on such matters) as the protocol baud rates typically vary from module to module,but I think old Hondas may have only utilized the UART protocol/hardware(9600 baud rate)but Ive not had reason to dig deeper than understanding how it works and how to measure it. In my capacity, I dont need to know how to apply it or write it, so I dont really know if its simple or not.

 

So I saw Hondash today and while the name is really familiar, I think I overlooked it before because of mostly only working with stock ecus or crome all at half duplex (which severely limits hz)

makes me want to look into the DLC a bit more out of curiosity.

really this isn't much different than a bluetooth ttl and an app for gauges..except you can use a bt elm327 and use any app instead of what's only available for obd1

that was my main reason for wanting to make it..could be cool for other things..I'd love to be able to reprogram an eeprom in my car from my tablet and ibe seriously considered building an eeprom emu to do it but damn these ecus are old..good..but old still..

definitely also interested in speeduinospeeding tho its only batch fire and still kinda new but good idea

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The problem with this is you can legitimately buy let’s say a Motec and use it in a legal fashion and all is good in the world, having OBD2 on the motec is useless for diagnostics vs a laptop but within the OBD2 output is the emissions section in which if Motec made work would only be for breaking the law so they don’t go there, I talked to Haltec last year at SEMA about this and that’s what they said. That being said if anyone does do this PM me.

 

I'll be doing it. Again, emissions isn't my priority but could be worked in. Frankly, it doesn't affect me - I live in a place where there's no emissions nor have I ever seen anyone have an issue running aftermarket or standalone here.

I'm sure my cars probably wouldn't pass. Maybe sedan she's stock.

either way, how people use it, doesn't matter to me, I'm not even based in USA so the laws there mean f*ck all to me and none here prevent me from doing this

 

Again, there is no legitimate application for a consumer to have a modified or programmable ecu in their road-going car. If it's not exactly as the manufacturer certified the car, it's tampered and it's technically illegal. If you have a Motec or whatever in your car and you're operating it on a public highway, you are breaking the law**. Local lack of enforcement does not equal legal in any way. What Haltech and Motec told you is precisely correct, there is no value in putting dev time into something that really only has use to cheat the law.

**Note that I'm not bothered by anyone creating or using such a device. Just pointing out the facts


The Hondash and Honobdapt will definitely be good places for you to start then. The hard part (the OBD2 side) of the communication is mostly already figured out. The ecu side is easy for stock & CROME as those protocols are well documented. Hondata should be a no-brainer as newer versions have CAN onboard and the protocol should be available. NepTune is physically easy as it's just a high baud UART, but the developer is (understandably) stingy with his protocol.

Making a device that spoofs obd2 for using apps and dongles and such is a little bit of a gray area, as you can argue that the device is strictly for interfacing with these devices or for diagnostic use. The second you fake a secondary O2S or spoof a readiness code, you're definitely into the flagrant cheat device, so there's that.

My $.02: I wouldn't bother putting much work into stock or eCtune, and I would do minimal work with CROME. Focus on getting it working for Hondata & NepTune. Phase 2 would be a CAN in/OBD2 out, that could be semi-universal for higher end ecus (or anything with CAN, really)

 

I suppose it could work with anything with can..but..if it already has can does it really need interfacing or just wiring..!? Guess it depends on what the target ecu supports.

once I get my b17 running smooth I'm gonna get the port installed and running.