Hello, My name is XXXXX XXXXX I will gladly assist you with your vehicle concern.
Hello... I will assume that you are popping a Catalytic Converter inefficiency code since you did not post the code description.Some after market cats tend not to react enough for the PCM to determine if you are compliant. It is something we have seen for the last few years, as the new vehicles switch from O2 sensors to Air/Fuel Sensors. Much more sensitive, and makes the bureaucrats and "grenen people" happy
A catalytic Converter is a reactor. As the exhaust gasses pass through, they heat up, essentially causing a fire. The outlet temp HAS to Be hotter than the inlet temp, by at least 150 degrees. Chances are, yours is not.
This burns off the Hydrocarbons, or unburnt fuels and helps reduce the NOX's... or oil that may pass due to the combustion process.
As much as this will hurt the pocket, you need the correct converter. Without it, your vehicle will not operate properly. With that lamp on, it will tend to run richer, meaning more fuel.
The shop that installed the converter should be able to credit you and install a Toyota one. Most likely the cheapest route to go.
I think you are rite