1997 Toyota camry check engine light code P0420 and getting awful gas mileage?

Yes Toyota have problem with that code i was told by a dealer tech that the 97 -01 Camry 3.0 V6 engine were the worst thing ever built the way this engine is built is making your catalytic converted to go bad faster. Just to let u know i dont know if u do highway driving this engine accelerated in slow down by itself while keeping the gas pedal steady Toyota know about this issue they have a tech bulletin on this engine.