Hello all,
My lovely FC (86 GXL) has begun developing an issue. My tachometer will work without fail during idle, gentle acceleration, and while my revs stay under about 3500-4000 rpm. However, upon really spinning the engine up, the tach will go dead and for the remaining drive will continue to alert me that my engine has stalled. Any ideas?

 

bad ground on the trailing coils,bad plugs wires or your plugs are fouling to knock out spark to the trailing coil
The Trailing coil is the one that sees the RPM and sends signal.

 

Thank you very much! Turns out plug wire sockets were very corroded on trailing plugs and not even lighting spark tester. New wires and plugs on the way, hope that solves the issue!