My 1999 Evinrude 70 hp 4 stroke had the engine hot light come on at start up on Saturday. The motor seems to run fine and obviously is not over heating. I purchased a new cylinder temp. sensor and plugged it in. It didn't make any difference. I have a new exhaust manifold temperature sensor coming, but after ordering it I have tested the resitance of the sensor and it seems within range. The light will come on even if I don't start it with the engine cold. There are no codes in the system by trying the check engine light approach and the motor does not seem to be running in S.L.O.W. I am at a loss and am supposed to be leaving on a salmon trip on Thursday. Has anyone seen this or can anyone give me any suggestions.