Hey sorry I didn't see your message. What all have you checked? Is the fuel pump priming? And how is the pressure at the rails? Also have you checked how your spark is, like the condition of your plugs, wires, and coils? Any codes popping with the fail to start?
I have a 1998 WS6 with 243 heads ported and polished. and performance cam. The car randomly fails to start. It cranks fine, but refuses to start at other times. When it fails to start, it sometimes starts a day or two later.
