ok just swapped most of my car parts into another shell. After hooking everything up my tach wasn't working so I check the wires and noticed a few had come loose. so i fixed them all and tried again it still didn't work so I tried swapping the rear coil to see if that did the trick but again nothing anyone any suggestions? I should also mention I have a SAFC 2 hooked up. the tach move a little at start up but then drops back down.

 

The only time I've had my tach stop working was when I swapped out my ECU and had one plug loose. Might be worth a look, especially if you had to reconnect the SAFC.