Just bouncing some ideas around. my fd is missing/breaking up at about .6 - .7 bar. I haven't lost any engine vacuum, nor touched the tuning. I'm running the microtech computer (both fuel and ignition) with the two bosch coils. Has anyone else perhaps had issues with the coils? I've replaced the plugs and wires so far, but not gotten anywhere. Think i'm looking in the wrong place by going over the ignition?

 

FSM has methods for checking the coils to tell if they are still good or not. Other than that, check the fuel pump and is it possible you just got a bad tank of gasoline. I know this recently just happened to me. I was out of town, bought a tank of gas from shell and it was crap. Breakup beginning at 3.5k in my Z under 60-70% throttle. Got back home, ran the tank out and refilled. No more issues...

 

I have had this happen to me 3 times in the year and 1,500 miles I have owned my FD from bad tanks of gas. Unfortunately, all of our gas comes in from one supplier in my area.

Add water removal treatment to gas and problem instantly goes away (once I remember what caused the problem last time and try the additive).