Mazda Repair Questions? Ask Mechanics for Answers ASAP
Welcome, I'm Chris (aka Moose) I'm an independent contractor here at Just Answer.
Your assumption is right. The converter(s) clogged can very likely be the issue with these symptoms. Remove both upstream O2 sensors and take it for a shirt drive to see if the car performs much better. If so remove one sensor and retest going back and forth to see which side is restricted.
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