2006 Mustang GT Coupe
Lets start at the very beginning
Bought the car a couple months ago for a steal.
Had no catalytic converters. Too loud and wanted to avoid future issues with smog, so I sourced an original catted h pipe with 34k miles on it (Car it came off of currently has 40k miles)...
Earlier this year my CEL came on and I saw that (P02270) it was my downstream passenger O2 Sensor reading lean (This was completely random and there were no changes or modifications that occurred to cause it), figured the sensor was bad or the cat was bad and thought id wait until I got closer...