I have been trying to figure this out, and have replaced all 4 of my O2 sensors. Anyone have previous experience with these codes continuing to pop up after clearing them, and then cranking the 07 tahoe after about 7 times?

 

Interesting since both heated O2 sensors are flagging resistance out of range. I'd suggest tracking down a problem in the wireing harness, i.e. routed to close to exhaust, or cut wire ect. If you have an ohmeter, I'd suggest unhooking the connection, read the resistance on both O2 sensors. I do NOT know what it should be, also these have been replaced, was this the reason for that? I assume after you replaced them, you cleared the code, and it came back?

 

Thanks. Yes - I have cleared the codes multiple times...same results. I have also checked any fuses I can remotely think would be related to this issue with no luck.

I can try to check with an ohmmeter when I can over the next weekend or so, but as for getting into the whole wiring harness...that's something I don't think I value to tackle.

Still looking for any other ideas or others who have had the same issue with resolve.

Thanks in advance.

 

What suggested was physically look it over as to make sure it dosen't have any melted spots, routing ect.

 

+1 check the harness as far back as you can and check under the hood as rodents have been known to chew at wiring

 

The O2 heaters are protected by a fuse. It is possible that one of the old one blew the fuse.