Q: P0432 Main Catalyst Efficiency Below Threshold (Bank 2) on 2001 Dodge Intrepid

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P0432 Main Catalyst Efficiency Below Threshold (Bank 2)
What should I do to fix this?
(4) Answers
(3) Comments
Here is some info and other similar questions asked about the P0432 DTC
Trouble Code: P0432
Catalyst Efficiency Below Normal (Bank 2)
Trouble Code Conditions:
Engine speed at 1200-1700 rpm in closed loop with the throttle open for over 2 minutes, ECT Sensor more than 147ºF, MAP Sensor signal from 15.0-21.0" Hg, and the PCM detected the switch rate of the rear O2 reached 70% of the switch rate of the front O2.
Possible Causes:
* Air leaks in at the exhaust manifold or exhaust pipes
* Base engine problems (high coolant or engine oil consumption)
* Catalytic converter damaged or has failed
* Front O2 older (aged) than the rear O2 (O2 is lazy)
I was haveing codes p0121 and p0123 with p0432, now that the TPS has been changed and a tune up has been done the p0432 has not come back and if it come back what should i repair?