Need to check for fuel and spark when problem occurs. Can you do this???
Also have you had computer scanned for codes???
What were the coides for the coils??? Have codes returned?? new codes?? All clear??
Also you will need to check fuel pressure and fuel injector operation. You will need a fuel pressure gage and a fuel injector noid light tester, these tools are available at most auto part stores. Some stores offer rental programs and some offer tool loaner program (i.e. Autozone)
Check for spark but you said it started with starter fluid pointing more towards fuel system rather than ignition system, but test any way
Were you able to check spark and f/p during no start???
You never told me codes???
Need to check ASD relay this feeds inj and coil on DG/OR wire .Is there power at coil....must be check within 10 secs after key turned on
Ok now I would re-check codes then erase and re-check codes after 50-100 miles or if it stalls again Let me know
You obviously have a heat-sensatized component that will not be diagnosed until it occurs