There is no substitute for a catalytic converter.
Yes, it happens when the catalytic coverter is clogged
you will get the check engine light on and not pass the dEQ
There are 2 oxygen sensors.1 is in front of the catalytic coverter and 1 is located behind the coverter
looks like it's for the CATalytic coverter.
there are 4 of them. 2 before the catalytic coverter and two after
Then it is partially clogged, your fuel/air mixture is too rich, or you have a cylinder miss. Get this repaired ASAP.
bits of the catacomb that makes up your coverter have fallin losse. if it sound like there is dirt in it that that's the case. The catalytic converter needs replaced.
If the oxygen sensor fits the catalytic coverter and female vehicle port yes
There is a sensor before each converter and one after each converter.
If the cat was damaged and restricting the exhaust it could cause a random misfire (P0300) but you would also have a severe loss of power.
it has 2 oxigen sensors one is before the catalytic coverter and the other is underneath(your car) just follow the exhaust system.
maybe catalytic coverter clogged, leaking coolant hoses to/from heater core, hopefully this helps.