Over the last 15 months my step son and I have been working on rebuilding the engine on our 2003 Zetec ZX3, as well as doing some very basic upgrades. Well this weekend we got just about everything put back together. When all was said and done I wound up with the above part in a box and for the life of me can not remember what it is for. It is obvious it connects to the firewall. What is this thing!?!?!?!