I got a brand new o2 sensor installed and it has increased gas mileage by a whopping 1mpg, I'm just barely above 14mpg now (14.2 or so)
The engine runs a bit smoother, but still has some vibration on the pedal around 1800rpm. Still feels slow as a slug and EATS gas like nothing. 4 gallons got me 30 miles. even though the OBC says 14.2mpg
Any other things I should check? I have no codes, free of vacuum leaks, new o2 sensor, new spark plugs...
Could anything in the ignition system be a culprit?
Thanks a bunch, again.