Lincoln Ls Gasket Leak How To Tell If The Catalytic Converter Is Bad Or Just The Oxygen Sensor?

How to tell if the catalytic converter is bad or just the oxygen sensor? - lincoln ls gasket leak

In a 2001 Lincoln LS I can not pass smog.
It began when a mech replaced my spark plugs cause an oil leak due to a defective seal. Then the mechanical one of the connectors installed in the winding wire, so it had to be replaced, this time for me, after retreading head. Now the machine is light went on for a while, but returned. I think that cat is bad sensor or bad.

I drove the engine light on (with the spark plug defective) for some time, so I think a lot of unburned fuel may have caused an obstacle to the cat.

But before we get more money for a new cat, we recommend that you spend the first $ 60 on a new O2 sensor?

My journey was more than 100K miles this year.