Hi All-

I’m new to this forum but could use some help. I’m working on my girlfriends 2005 HCH and have some questions regarding the oxygen sensors on the car.

On my GF’s car she is getting the following codes from the ECM and the check engine light is on
P0420
P1130
P0139

All 3 codes point to the secondary oxygen sensor. Just to clarify the secondary oxygen sensor is just after the TWC at the bottom of the manifold in the engine compartment.

In the manual it says the secondary and third oxygen sensors need to be replaced in pairs to keep the performance matched… Anyone know if this is true or would I be ok to just replace one?

Anyone tried to replace the secondary O2 sensor with the ones from autozone? The connector came as a male and I need a female connector. The O2 I bought from autozone is the bosh13680.

http://www.autozone.com/N,16000117//shopping/partTypeResultSet.htm

Has anyone else attempted to replace these? My dealer just offered to do it for me for $460, which seems a little steep for one (he did not mention doing both). Any insight and/or pointers to places to get the sensors would be welcome.

Thanks!
--Larry