This 85' engine has two temperature sending units in the cyl. head. My 1980 300TD only has one temp. sensor in the head. The 1980 model has had a turbo motor put in place of the n/a motor that was oem. I bought the car this way so I know nothing about the transplant on that car...so yea The 85 300TD I am trying to get going has two sensors in the head. I wonder why this has two sensors?