|
Well only the upstream O2 sensor is used for short term fuel trim. Not sure if the downstream sensor is used for long term fuel trim, so perhaps there are consequences to spoofing it?
I have a dim view of aftermarket cats because many are a scam, and the ones that aren't likely cost a lot, and in the end you're just trying to turn a light off the dash so you can pass inspection. Fuel economy isn't affected at all unless the cat is actually clogged.
|