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Eric Parham
10-22-2003, 11:22 AM
OK, I've seen several Honda guys reflashing their own OBD2 ECUs at the track, but all I see for VWs are reflash services where we have to mail in our OBD2 ECU and wait... Is there some reason that we can't reflash our own at the track? I thought OBD2 was supposed to work "the same" for all makes?

Also, when removing the cat on an OBD2 car, is it necessary and/or beneficial to keep the oxygen sensors (two, one originally upstream of the cat and the other originally downstream)?

Eric Parham
10-24-2003, 04:54 PM
Obviously, this will apply to A3 Golf projects using a '96 or newer OBD2 compliant ECU, especially if the World Challenge guys are correct that OBD2 is faster than OBD1. Some of the coding will be applicable to the OBD1 cars, but they'll probably always have to pull chips.

I'm not sure what to think about the silence. Others must have thought about this before...? It's obviously too much work to start from scratch (or alone) on this item, so I was hoping to hear from others and maybe get some sort of joint effort going.

Tech stuff:

1) We need an I/O port map, or at least a table mapping for the '93-'99 ECU EEPROMs.

2) The main issue for tuning will probably center on in-car adjustability. The main problem with reflashing VW OBD2 (in-car through the diagnostic port), as opposed to BMW or Honda, for examples, seems to be some sort of an encrypted security handshake (seed/response) problem embedded in the factory ECUs. There are two or three potential ways to de-smell them that I can think of, but not certain what will work.

Besides VW/Audi, I also see that a couple of aftermarket companies are already reflashing VWs through the OBD2 diagnostic port (Revo and APR), but are apparently keeping the method a secret so that you still have to take it to one of their dealers (plus, they're only supporting the turbo crowd and off-the-shelf programs, at the moment, for obvious reasons).

Any thoughts?

[This message has been edited by Eric Parham (edited October 24, 2003).]

Knestis
10-24-2003, 04:59 PM
Since the "SSC" on the door is going to prevent me from taking advantage of any of this fun for two years, it might not make any sense but I'd be interested in a collaboration on this project.

I don't have the technical skills but I'm not stoopid either, and I'd be willing to help out with some $$ if there is potential to productize what is learned.

K