4G64 VS 4G63T Harness, are they really deifferent?

[nathan259]

Hi all, I've read everywhere on this site that when doing a 4G64 to 4G63T swap, you must change the ECU AND the harness. However, when I look on the electrical diagrams in the manual, both harness look the same. Is it really needed to change the harness too or can I just put the new ECU in there with the old 4G64 harness?

The car is a 1999 Eclipse Spyder GS, the ECU comes from a 1999 Eclipse Spyder GST.

Thank you.

 

[FUZZYDESERTDSM]

i say for on the safe side just put the 4g63 harness on it.

 

[nathan259]

Yeah, never mind, I took a closer look to the diagram of the engine bay and there are differences, I don't know if there are a lot of differences but there are.

I will be putting the 4g63 engine harness in.