o2 sensors??

[02sscamaro]

my friend checked my o2'S with the ez scan and the upstream was going from 85 to 100 quick and the other was 35 to 45. this was with the key in the on position and at operating temp. it was running sluggish like no pep. can it be checked this way?? and does this sound like a lazy o2? no light has come on. oh the o2s in the back it said not complete on the scan tool because the car was not running.

[greatwhiteZ28]

when my car was scanned it was just on the ON position, but not stared

[JonB]

A lazy o2 will usually just switch off and on causing you to have a normal reading one second then the next nothing. I had that problem when I had my car tuned once he started tuning the car on the dyno my drivers side o2 started acting up but he was able to get the car tuned it was just a pain cause one second he had a good ready then it would go away. You will notice a lazy o2 as well it will feel as if your car has a miss.