It could very well be that the computer needs to be reset.Modern computers adjust as the paramiters change as your car ages.They store these paramiters from start up to start up.I did a quick google on how to reset and all I come up with is that you need a scanner.If you have a repair manual it should give you details on how to reset and often procedures for warm up and driving after reset to help the computer reset values.

The oxy sensor is the biggest tool the computer has to adjust fuel spark to keep the car running at its best as things wear.
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With the population ballooning out of control, there
are bound to be more and more fishermen clogging up our rivers. All of
these fishermen have one thing in common: They come to the Olympic
Peninsula seeking solitude.”
Pat Neal