1986.5 NA Tach driven from Aem doesnt work. no ignitor now COP

[1986.5supra_kid]

Hi im trying to get the tach to work on my NA chassis with a 2jzge and v2 aem. the tach signal comes from aem output then to the body plug. it responds up until 1850rpms then falls to zero. i see that the NA an turbo tach have differnt boards. i assume this is the problem? can i mod the factory one or just swap the tach.

 

[hvyman]

You can modify the na one or swap a turbo tach. theres a thread somewhere for modifying it.

 

[1986.5supra_kid]

I think for accuracy I'll just swap tach