swapping from ODB 1.5 to ODB1.0

[Manitcor]

My stock ODB1.5 ECM is nothing but a pain, no one does anything for it and becasue of its crappy hybrid desgin I cant even have the codes read from it by anyone other than a dealer.

I would like to step back to an ODBI ECM so that I can modify it to suit my purposes and make my life alot easier when trouble shooting.

Has anyone done anything like this before? I know I will most likely have to change the entire wiring harness and some sensors.

Right now im using a 4t60-e trans however I am looking into swapping in a manual so I would like to have a computer that would support this.

Thoughts, comments, suggestions are all welcome.

Anyone know of a good ODBI guru that I can get in touch with once I have this done so I can get things like shift points changed and A/F tables optimized for my mods?

[brian89gp]

Boost or NA?

If NA you have 2 options, the 91-93 3.4 DOHC wiring (the internal wiring on the tranny is different). The 94-95 DOHC might be a viable option though no one has attempted it yet.

For boost the best bet would be to do the 5spd swap and use the TGP ECM.

[Manitcor]

I will be NA this year though I want to go back to boost for the 2005 season. What does the TGP ECM have other than fuel curves that the 91-93 ECM would not have?

[brian89gp]

Wastegate control and a pretty agressive knock retard system. Oh, and support for a 2bar map sensor. Making a 91-93 ECM do boost is far from simple.

[RidgeRunner]

OBD!!!

Not ODB. :P

[3100 MPFI]

OBD 1.5?????

Never heard of that one. Just OBD1, and OBD2. Not that I really looked into it that hard.

[Cliff8928]

OBD!!!

Not ODB. :P

What's wrong with ODB?

Sometimes at work i think about telling my customers that they will have to go to the hardware store to get a PVC valve...


Cliff Scott (now i have 'Ol Dirty Bastard stuck in my head)
89 BerettaGT
89 Volvo740

[SappySE107]

What about using the 94/95 DOHC ECM? How would that differ for wiring up with the current computer wiring setup?

[bszopi]

I started writing a swap guide a few months ago, but never got around to finishing it. You can find what I have done so far below...

http://60degreev6.com/SwapGuides/PCM%20Downgrade%20for%20Performance%20Upgrade%20Swap.doc

[SappySE107]

damn, got enough %20 in there!

[Rhedalert]

OBD 1.5?????

Never heard of that one. Just OBD1, and OBD2. Not that I really looked into it that hard.

'94-95. The sfi flash computer that isn't OBD2. Yet another reason why '95 was just a bad, bad year! "EEEEE!!!! MOM!!!!!!! "

[Manitcor]

Im not sure what the offical designation of the 95 OBD ECMs were but they are commonly called 1.5 becasue the have an OBDII style connector and have a mix of OBDI and OBDII code. So It cant be jumpered to read the SES codes and most autostore readers wont work with it. You have to use a techII to get anything from it. Addationally its not Flash ROM based so it cant be flashed only chipped but no one makes a chip for it. 95 was definatly a bastard year, I have to specify I have a 95 for so many things becasue even in the monte they changed tons of stuff between 95 and 96.

Thanks for the doc bszopi that should provide enough info to get me started.