Different OBDII ECU memory size versions?

[korbendallas68]

I read some where (Mymonte.com I believe) that the '96 OBDII ECU is slightly different from a '97+ OBDII ECU? 256k of memory for the '96 version and 512k for the '97+ versions?

Is this a advantage for tuning or anything if it's true? If so, how?

[OldSkoolGP]

The '96 ECU is totally different. It only has 256K of memory size, and no one writes tuning software for a 96 ECU. 97-98 ECUs have 512K memory and you can get tuning software, and ECUs newer than 2001 have 1MB of memory size.

[korbendallas68]

Oh wow. Never knew that. I'll defiantly have to not use a '96 ECU then. Thanks man.

Why does the size of the memory make such a difference for tuning?

[bszopi]

I think you may be thinking of the memory like a computer's RAM, but that's not what it is. Its the actual room on the chip for the data. Therefore, a 97+ PCM has twice the room for data than the 96. This allows for more tables and such, which therefore results in the ability for more tuning options.

[korbendallas68]

Makes total sense.

[Rhedalert]

Some cars (like w-bodies, H-bodies, minivans) the '97 computer is just like the '96 except the internal memory. It's plug and play between '96-97 (Though I think you can't mix programs). '98 had another change that makes it incompatible and that PCM ran thru 2002.

I think the N-bodies and J-bodies got the "newer" computer in 1997, so watch which platform you steal it from. You'll be able to tell by differences in the casing. '96 and '97 look identical.

[korbendallas68]

I've seen that at the junkyard when looking for ECUs. 96 Use the 3plug-setup and 97+ Use the 2plug-setup. I'll have to be sure to grab the newer harness (if I can get it before some moron hacks it up). I'll be sure to stay away from minivans (1996-1997 right?).

Brian, I noticed that you are use a 3400 ECU. What year of car is that from? I've got one from a 2000 (If I remember correctly) Grand Am GT. I know it'll plug into the 97+ Grand Am harness (The 2-plug design). Anymore info about the swap?

[timg]

DHP can tune a lot of the 96 PCM's. In fact, they're the only ones tuning both the 96 and 97 DOHC PCM's.

Tim

[IsaacHayes]

W body, and L body 96 can swap to the 97 minivan ecm... Grand am i think is totally different.

[geldartb]

96+ grand am's i beleive had the theft stuff which might pose a problem with drop and swap.

i know a few of the 2000+ grand am's and alero's ive been through in the yard have different colored pcm plugs. instead of the blue and clear plugs, they had a clear and black plug.
the clear one was the exact same as far as alignment slots go but the black one was off a bit.

i found that out when i was grabbing plugs to build my offboard setup to flash out of the car.

[Rhedalert]

I've seen that at the junkyard when looking for ECUs. 96 Use the 3plug-setup and 97+ Use the 2plug-setup. I'll have to be sure to grab the newer harness (if I can get it before some moron hacks it up). I'll be sure to stay away from minivans (1996-1997 right?).

Brian, I noticed that you are use a 3400 ECU. What year of car is that from? I've got one from a 2000 (If I remember correctly) Grand Am GT. I know it'll plug into the 97+ Grand Am harness (The 2-plug design). Anymore info about the swap?

The PCM is from a '97 Venture. A 2000 may, MAY plug in, but the pinouts are definitely different. To the point that it's not really worth it, just grab a '98-02 harness that will work with your car.

[z34phoenix]

yes DHP does support 96's atleast i know for a fact that my 96 DOHC is supported... i've done tons of tuning with it. as for extra tables...

the only tables i dont have in my 96 file vs a 97 are trany files... and that is cause the 97 Z34 had the 4t65e...vs my 60e. the extra tables control the line pressure... something the 60e does via engine vac. as for other tables... they are the same. there could be many other hidden tables the Powertuner cant see though... as a friend of mine found out after his swap to a 97 trany, pcm and harness... there must be a hidden table that locks out some shifting if the coolent temp is too cool. this keeps him from runing a 180* stat.