Those are both pcms, meaning they can control trans as well as engine. 8625 and 7427 are pretty much identical, can run the same codes and can"usually" swap over without a glitch.

Edit.. manual and automatic are 2 different sensors. Read different ohms. Can cause all sorts of havoc. V6 uses 2 knock sensors, v8 used the one depending on trans and that decided if your using a...

What knock sensor are you using? Manual and automatic are different and read differently within the pcm. The knock sensor must match what is on your chip.