My MSD,as well as several I sold never worked right either. I finally sent in, "had the 6200 studder problem", they returned it, saying it checked out fine. Since Ihad called first and the tech said they had not had any complaints with the unit, I knew I was in trouble. When I called back after receiving the box back, Iwas again told there were absolutely no problms with the boxes. I couldn't accept that, since I remember this thread from before and knew of many guys with the same complaint, so I pressed the kid until he suddenly had a brain fart..... Ohhhhh, do you use a FAST unit? Of course I do, I tell him, he goes on to say that they have founda problem with the box being used in conjunction with aftermarket engine management but have not yet figured it out.
My friend Paul got his unit to work by going through some major insulation routines. Maybe he can share what he did. Too much for me to write down. I also no of several guys whose work fine tat are usingFAST units, Jason being oneof them.