Stupid furnace is driving me crazy.

Changed igniter, pressure switch, tried different thermostat, changed board (not positive that it is a good one, though).

Completely random issue: will run great for a few days and then will start acting up for no discernible reason.

Ignites, runs for a few secs and then turns itself off.
The board gives 8 blinks, no idea what that means, the manual troubleshooting guide only goes up to 7 blinks...

Reboot it enough times it eventually restarts, but not this time.

Currently with no heat.

Who is the forum go-to-guy?

I NEED HELP!!!