Rear Oxygen Sensor -- DYI?

[Thomas Nickerson]

My Saturn dealership tells me that the rear oxygen sensor on my 2003
Ion 1 needs to be replaced; it is "not switching lean to rich". If
anyone has done it, is this job a DYI candidate? The garage wants $191.
Ouch.

Thanks,

Tom

 

[BläBlä]

My Saturn dealership tells me that the rear oxygen sensor on my 2003
Ion 1 needs to be replaced; it is "not switching lean to rich". If
anyone has done it, is this job a DYI candidate? The garage wants $191.
Ouch.

Thanks,

Tom

Rear O2 = Down Stream to me... The reason they gave makes no sense to
me. Why SHOULD it switch from rich to lean when it is "down stream" of
the converter? It should remain at or near .5 volts with very little
fluctuation. Is it throwing a code? Is it stuck reading above or below
..5v? Yeah this can be a DIY'er job...that is if it is even in need of
replacing.