Bad IACV? check CEL codes for #14
I once had a problem similar to yours, I changed my IACV out with a used cleaned one. You can check the IACV taking off the air intake and checking for suction on the top hole there should be plently. It sounds like its failing because once the FITV passes its job to your dead IACV your car dies too. Another way to test it is to connect the + and - to your battery. It should click on. If you decide to clean your existing IACV cause it could just be stuck closed use TB cleaner and make sure you let it dry for a good 10-20min before reinstalling it.