Most likely a ignition or fuel problem. Blinking is a major warning something is wrong, try going to a auto zone as they can check codes to let you know the problem. Hope this is a little help
I'm not sure if it applies to German automobiles as well, but typically in domestic cars if the check engine light is blinking or flashing it means you are doing damage to the catalytic converter....
Assuming they are both 3.1L V6, they are not exactly the same. The upper intake and front cover are different. If you are swapping motors and don't mind some extra work, it can be done. I owned...