I replaced both oxygen sensors an still coming up with low voltage to oxygen sensors, I’m getting the 5 volt reference an 12vs and gnd, I’m starting to think it may be the catalytic converter, I check the inlet and outlet temperature…inlet temp is about 655 degrees an outlet is about 410 degrees but isn’t coming up with a cat code

 

Welcome to the forum.
How many miles are on the car? It sounds a little unusual for the outlet temperature to be lower than inlet on a catalytic converter.

I'm moving your post to the Sonic section of the Forum where you will get more views.

 

97k and using up a lot fuel