Holley Sniper EFI

Installed my inline fuel pressure gauge, fired up the pump 62 psi going out to sniper rock solid. Checked my tach wire from neg side of coil to harness, all good. Wired my crank 12v to a relay so i would get a steady 12v. Ended up getting the car started for a little bit. It later stalled out again after 20-30 secs. Threw an analog tach meter on the neg side of coil and the other lead to ground. i then got the car to idle, the unit started learning when warmed up and i adjusted the iac to 2-5%. When I removed the analog gauge while it was running the car suddenly died and when cranked wont idle for very long rpm gets up to around 550 then it dies and says stall. I hook the analog tach back up to the car and it idles and starts fine, wth?? I'm kind of perplexed here anyone have any ideas. Im running a pac distributor and coil from pace performance, basically an msd ready to run clone.