I just put a ford remote start /keyless entry on my truck. Where is the tach wire on the 7.3 is a 99and 1/2 and superduty supercrew auto.

 

I see you got an answer in the Diesel forum. The reason I know this is because I was looking for answer up there myself

I looked in the diagrams, and the more I look at the later model trucks, whether they are diesel or not, I am getting the jist that they are using just one set of sensors for the computer, and then the computer communicates through a network to the cluster. This is the way the cluster gets all of it's info on engine speed, temp, etc. In the older trucks they had two sets of sensors. An older truck would have had a seperate wire for the tach, and another for the engine computer.