Tell me the year of your car, depends on which year. There are 2 different oxygen sensors, dont get the wrong one.
For speed sensor, dont do it by yourself cause the rust of the old sensor on the kunkcle, it break easily and hard to take the partial out.
If you can tell me the code from the OBDII checks, tell I can tell you more about whats wrong with your car. Sometimes the same code have different ways to determine it.
I doubt you get speed sensor code, because check engine light scanning only for PGMFI. Speed sensor code only come with ABS light on.