General ECU Replacement

[Jourdain Keel]

I currently have a 96 GSX with the OEM ECU in it. I want to swap the 96 ECU with one from a 98 since I heard they're more reliable. I'm scrolling through ebay and I see an ECU for a 97-99 GST. Are they the same ECU since they're both the 2.0 turbo? Thanks!

-Jay

 

[delta448]

What you're really looking for is a plastic cased H8 ECU. Those are the ones that are flashable with a tactrix 2.0 cable. All the 97-99 ECUs can be swapped between themselves with no wiring changes, but the metal cased non-eprom 97 year ECU is not flashable, and is slightly more susceptible to corrosion.

Either way, to work properly with your 96 you will have to swap spark plug wires in the least. You may still get a random misfire problem though. The issue is in the way the CAS reports info to the ECU, and swapping out the stock 95-96 CAS to a 1G CAS is the best option if you get it.

 

[Jourdain Keel]

What you're really looking for is a plastic cased H8 ECU. Those are the ones that are flashable with a tactrix 2.0 cable. All the 97-99 ECUs can be swapped between themselves with no wiring changes, but the metal cased non-eprom 97 year ECU is not flashable, and is slightly more susceptible to corrosion.

Either way, to work properly with your 96 you will have to swap spark plug wires in the least. You may still get a random misfire problem though. The issue is in the way the CAS reports info to the ECU, and swapping out the stock 95-96 CAS to a 1G CAS is the best option if you get it.

So the best option is to swap to a 1G CAS in conjunction with a 97-99 turbo ECU? Or do you think I can get away with repairing the caps on my 96 ECU with a 1G CAS.

 

[delta448]

The plastic cased H8 ECU was used in some 98 and most 99 turbo cars. AFAIK, no 97 year cars got one from the factory. The 97s got a non-eprom and non-reflashable unit, similar to the 96s except they were set up to use the CAS that sits on the trans side of the intake cam instead of the t-belt side sensor that the 96s used. The 95s used the same cam angle sensor as 96s, but the majority of 95s had an eprom chip that could be removed and reprogrammed. Those are the ones used for dsmlink/ecmlink.

What I'm saying is if you are going to the trouble of swapping to a 97-99 ECU, which will probably force you to switch to a different CAS in order to avoid issues, why not get one that is reflashable? Or get a 95 eprom ECU and ecmlink?

Personally, I am using an Evo 8 ECU. It's flashable with the cheaper 1.3 tactrix cable. But it's not a straight forward swap. It requires depinning the ECU harness connectors and swapping a few wires around.

 

[Jourdain Keel]

Sorry for my ignorance. I'm pretty new and I'm trying to understand ECU stuff. I didn't realize there were more ECU options other than swapping ECUs from later models but okay. So if I get a 95 eprom ECU, would it just be plug-and-play? I'm not to thrilled about depinning and doing electrical work. Plus the advantage of having ecmlink will be great since I'll be upgrading for power later on. If I swap to the 95 eprom, would I have to change any hardware?

 

[delta448]

No changes needed. Just unplug one and plug the other in.

http://www.ecmtuning.com/index.php?cPath=24

 

[Jourdain Keel]

No changes needed. Just unplug one and plug the other in.

http://www.ecmtuning.com/index.php?cPath=24

Delta448, thank you so freaking much for the info!

 

[motomattx]

If your going with a flashable plastic ecu, you want a 98' or 99' turbo ecu, and you would need to swap the plug wires where they go on the coil pack two for two so that it will run, a lot of guys run the 1g cam sensor in conjunction with this setup to avoid the possibility of a check engine light (some get one some don't) you could also use the 97' cam sensor, but its nicer to use the 1g since your timing is then adjustable (I like that feature).