Jen the vacum lines are plastic brittle and break really easy like spegetti I had rough idel and it was the lines but I got a light on the dash.I would not mess withthe wires as I have broken my taking them off.Installing the plugs is easy but the wires are something else you need instructions.Maybe someone will post them for you as I dont have any pics...You could have bad plugs installed wrong or they broke th wires by not knowing if mercedes did not change them....