u/Disrupt0101

Currently in the San Gabriel Valley area and have not been able to find an auto shop/mechanic that is honest and does quality work. Prices should be reasonable, not outrageous. Do you have a go-to mechanic? Any recommendations? It does not have to be exclusively in the SGV, I'm willing to drive further if it is worth the trip. Thanks, in advance!

2016 Honda Odyssey Touring, 75k miles, VCMTuner II installed at 50k miles, NGK Ruthemium spark plugs installed at 58k miles.

A few days ago I noticed loss of engine power when accelerating. A day later, the check engine light turned on. The T-mobile sync up device shows a DTC: P0420.

Could it simply be an oxygen sensor failure? Or does the loss of power indicate the catalytic converter failure? If the converter is done for, I will go Honda OEM. Thoughts? Also, any auto shop recommendations in the Los Angeles area? Preferably closer to San Gabriel Valley.

Thank you, in advance.

https://preview.redd.it/7ski39mevi2h1.jpg?width=1320&format=pjpg&auto=webp&s=8014619706e99cc9c108a5913f4d94fd2cf1268a