i dont know if its alternator, ignition switch, ecu, i just want some pointers of what to look into as to why my car has a problem starting and even staying on sometimes.

I have an 02 sensor and Loop control code, yet my car has issues starting all the time.

It turns over, and almost starts every time, like u can hear exhaust but just wont finish....

i also hear misfiring...gonna try an old set of coils i had...but any pointers, please let me know...

battery is good by the way