So it dies... with a vac leak it will start and run, maybe needs to throttle up so it won't stall but runs. Always need to check for leaks anyway and you ptobably have one but not the issue. How old is your fuel pump and filter? O2 sensor? If you can borrow a SCT will be great. When it warms up the ECU relies on the engine sensors to keep it running, mainly o2 sensors, not when cold.
Pump Gas 385whp 319wtq
Race Gas 551whp 439wtq
Tuned by Fernando@RacingPartsSolution.com