Resolved O2 sensors? 1g or 2g?

[hippy]

i got a 98 gsx and there is 2 sensors in it and i think one or 2 of them are bad cause i allways seem to be running lean and a little sluggish! So i had a xtra one laying around out of my old 1g would it work in the 2g?? And which one seems t be more important the front or back?? Why is there 2 of them?? And what would it do if i unplugged it would it go into closed loop mood and run rich?? Thanks for your help!

 

[teme]

I have heard that 1g and 2g o2 sensors are different and not to be mixed...

There's two because 2g's have ODBII, and 1g's ODBI. Different systems. ODBII uses two o2 sensors. They both must be in place. You can disable the second o2 sensor if ex. changing exhaust system to better one with no second o2.(You can find how-to on the net).

I'm guessing the second o2 sensor is for checking if cat. works as it should. Also another wild guess, that the ecu checks values from both o2 sensors and adjusts based on average of them. Anyone have plain facts on how the system works?

If you unplug o2 sensor(s), ecu doesn't know how to act so it goes to some predefined fuelmap.

 

[luv2rallye]

Front O2 sensor is the important one used for mixture and must be working properly. Rear sensor is used for emissions only.

 

[teme]

Front O2 sensor is the important one used for mixture and must be working properly. Rear sensor is used for emissions only.

What you mean by "emissions only" ?

 

[luv2rallye]

Monitoring hydrocarbons (for pollution) to check effectiveness of cataylitic converter.

 

[teme]

Yeah, so exactly as i guessed