O2 sensor problem

[PRO®]

What would make a car not throw a CEL at idle, but when it gets up to 40 mph or so, an o2 sensor code is thrown? The guy said that it did this when he bought the o2 sensor new. Resultantly, gas mileage= :no:

[Barefoot]

whats the o2 reading at idle and what is it reading at speed.

[PRO®]

whats the o2 reading at idle and what is it reading at speed.

don't know...is that info on the emissions test? i think the paperwork might be in the car

[Barefoot]

don't know...is that info on the emissions test? i think the paperwork might be in the carna i dont think so. a scanner that does data capture or logging.

[PRO®]

anything i can do without a scanner?

[J-ROCK]

try gettin another o2 sensor and putting it in and see what it does? thats what i did to my buddys car and it turned out to be a bad o2 sensor

[Barefoot]

ill give u a call next time im in the area. ill bring the scanner with me.

[PRO®]

ill give u a call next time im in the area. ill bring the scanner with me.

coolbeans:goodjob: