how to check if my o2 sensor is working???

[91-gsx]

if anybody has checked if their o2 sensor is working, how did you check and what steps did you take, in the mean time i will look through the shop manual.
thanks

 

[speedy13]

well if youhave a logger all you gotta do is hook it up and see your voltage and see if it oxcillates accordingly.

 

[crunchymilk]

you can borrow someone's A/F gauge and make sure 02 is cycling

 

[SethA]

you can borrow someone's A/F gauge and make sure 02 is cycling

Or just use a multimeter.

Seth

 

[91-gsx]

i cannot get a air to fuel gauge from anybody. the reason why i think the o2 is out is because my trims are stuck at 139% and the car just bogs and bucks at high rpms, like above 5000. it shoots black smoke and is running to rich, obviously, but the trims still peg at 139%. i have 750cc injectors and a chip for them, and the car is set at 430cc injectors on my maft, and still same trim. these reasons lead me to believe that my o2 sensor is out, the exhaust also smells really bad, i have a headache right now.... and my gas mileage sucks, less then 20mpg, slow driving.
thanks for any help you might offer