MicroSquirt.com read only forum (Jan.15,2018)

I need some advice here, i had my setup running well, tuning the VE table and screwed up. I had my car triggering off the coil + using Optoin-, i screwed up and mistakenly attached Optoin+ to the tach signal on the hei cap (don't ask me why..brain fart). I cant get the car to idle as the rpm signal is spiking everywhere. Once i figured my mistake, i disconnected the Optoin+ from the tach but now the car will not start, engine cranks, will start momentarily with starter fluid but that's it.

Checked fuses nothing is blown.
the setup is a v3 microsquirt running fuel only on a 1966 GTO, with an HEI only. I have had to replace a resistor in the microsquirt before, could it be blown again?

I had an issue with the R20 resistor before and checked it out. It is ok, does anyone know what else could be damaged, no visible damage on the board

What exactly are Opto In + and Opto In - wired to right now?

I went back to how I had it previously, Opto is disconnected, Opto is connected to coil positive. I checked all fuses, fuel pump, fuel injectors, ecu, all were ok

You need both of these connected to work. Connect Opto In + to the coil negative.

Thx Matt, all is fine after I rehooked all wires, I am going to change how i get the tach signal I am having issues with the coil negative giving a stable output

Try wiring the VR sensor in the HEI distributor to the MicroSquirt VR conditioner instead (in parallel with the HEI module).