Going to swap the engine from my '90 into my '93, do I have to replace the ECM or are they the same?
Both are VG30E AT

 

I believe there's some subtle differences. mostly the injectors MAY be different connectors (93 was a crossover year, iirc)

 

There are also possibly less subtle differences - take ours here in South Africa (maybe elsewhere in the world too?) ............... we don't have O2s here on the 3rd gen at all and I don't know how the ECU code/maps/hw were adapted and whether or not it will even matter (imo it will)

 

No you dont. The injector connection may be different, but all you would have to do is swap LIM with injectors and rails. I'm swapping a VG from a Max into my Z31...do I need to swap ECU. Nope.

 

Changed the engine yesterday, worked without a hitch without replacing the ECM