2000 Chevy Astro .. ASTRO OXY.SENSOR DO I NEED TO REPLACE?

[quote:b1d59fa3c9="mahalojoe"]Computer problem
2000 Chevy Astro 6 cyl Two Wheel Drive Manual

The code reader tells me to replace O2 sensor...Q? does default setting affect mileage significantly?.. does gas w/crappy ethonal wear it out sooner or give false readings? [truck is pre-alcohol use]. will new sensors correct for ethonal? are generic replacements equivilent? should I relpace all at once? where is best online place to purchase?
what else can you share? smile.......Joe[/quote:b1d59fa3c9]

Why in the world would you tell me that you had a code and not tell me what the code number is? There is not a code that exists that tells you to replace the O2 sensor. The code may give you different information regarding that sensor. Do you want me to tell you to throw money at a problem that you did not provide the complete information?