My car was working properly until I suddenly parked it and the engine has never started again.

I recently just did a stereo upgrade from factory system to aftermarket pioneer Bluetooth MP3 and I'm not sure if this has anything to do with it but after doing so my car all of a sudden won't stay on after starting it it just stalls out right away every single time I will check the fuses they are all good I've cleaned out the air intake of any fluid I just don't quite understand what the issue is I understand the mass airflow sensor could be the issue but I would like to get somebody else's opinion