Tach died some time ago for no apparent reason. Digging thru the archives I see a lot of discussion that centers around the "TD signal". I see that as another term for "engine speed sensor". Correct me if I'm wrong.

New Deka Gold battery. Car fires right up. Idles smooth and accelerates the same. Car runs great. No tach at idle or any speed. Stays at zero at all times.

It would seem if I had no TD signal, the car might not run long after starting, if it were to start at all.

This vehicle has a MAS with a tach port. I suppose that could be defective.

Is my thinking about the TD signal correct?

Thanks.