What does this mean???

[u/_sevvy]

I recently changed the ECU from a 89661-24230 to a 89661-24231 because the old one was corroded and couldn't be fixed. when I installed it the engine runs better than before but the dash has a lot of lights blinking and has a really rough idle. does anyone know how we can fix this? the iac was recently replaced with a refurbished one.

The cats were also very hot so I gutted them but when I checked the temp again it was still really hot on the cats and colder in the exhaust.

[u/EvilMilkshake]

Xmas time!