These things are nortorious for electrical faults try ya fuel pump relays under dash, failing that cud be ya mass air flow meter very common problem on the 8v's usually makes them cut out wen they hit running temperature. cant see it being the coil wud either just cut out or not start even tho this is also a common fault on them i changed loads of stuff on my old 8v and was the air flow meter in the end failing that get a diagnostics don it shud find whats up straight away