How can you tell if a wideband sensor is going bad?

[Structure240sx]

lately i have been getting weird readings from my wideband. a few days ago i was getting some lean results so i added a bunch of fuel and it helped slightly. i then hardwired my fuel pump and after trying to get full boost the car sputtered badly. i thought this was a spark problem even it didnt quite feel the same. last night for the hell of it i leaned it back out and it ran just fine.

the problem must have been running extremely rich in boost but my wideband was reading inthe low 12's, weird? then i leaned it back out and this morning it went to mid 12's then next boost time it went to 11.9's.

what really got me is when i had the sputtering i had it set to 0% correction in boost for the 550's and it was reading 11-12's. when before this started i had it to about 25% correction and ran 11afr's

[blubottlemax]

Have you tried re-calibrating your wideband? I don't know which one you have, but on my LM-1, you can re-calibrate the sensor. If it doesn't read 20.9 within .04 then your sensor is bad, at least on the LM-1, if I recall correctly. Mine wasn't reading right when I first set it up, but after I recallibrated it, its been fine.

[DirtyKA]

They say if your wideband doesnt respond to quick blips in throttle that is a sign of sensor failure..So maybe start it up and warm it up then just give it some quick throttle and see if the readings fluctuate..

[Structure240sx]

i started out with the lm-1 but couldnt stand the display, so i now have a plx m-300

i will try the throttle things later thanks