Hi all, 132k miles on the engine, and ever since 97k I've had a P0420 (Inefficient cat). The car always has seemed a little hesitant to get up and go but never had any major issues. Fluids are kept up religiously, maintenance always done when problems arise, etc. However, when I was leaving work today, I went to start up my car and there was no CEL! It's a completely different vehicle now. When I would go slow in the parking lot (5-15 mph), the car would always want to jump. I would also have a semi-rough idle but nothing major by any means. It accelerates quicker now and is waaaay more responsive. This situation happened a couple weeks ago as well. I ended up plugging in my scanner and found a P00420/30 code and a P0016 code, but no check engine light. Plugs are good, PTU, RDU, and Coolant were all serviced less than 10k miles ago. Transmission right around 15k. I just did an oil change this past weekend too. Motorcraft filter, Castrol Edge 5w-30. Thoughts? It's going to my mechanic next week so they can diagnose it further and potentially call a priest for an exorcism.