After installing new sims for the rear O2 sensors I beagn getting two codes. Both are high voltage codes for the rear O2's left and right bank respectively. The exact codes are P0138 and P0158. I called the company I got them from and they say they are not defective units.

Does anyone know how to fix the problem or test if the sims are in fact defective?

 

Both sides should mean that they are in fact, not defective. I'm not sure what your problem is though. I give this advice to everyperson who comes on these boards though. Go to an LS1 speedshop, and HAVE THE CODES DELETED. It usually costs less than the cost of O2 sims and is FAILPROOF.

 

Your PCM is not completely ignorant like you think. It does have the ability to learn. It probally noticed that it kept seeing the same voltage values, no matter what it did to the fuel trim. Either get the codes deleted, put cats and o2 sensors back on your car, or get a scan tool of some sort and check the signals if you want to be for sure you some how didnt pull the short straw and did some how get two defective units (hey, it could happen).

 

Thanks for the advice. If I do get the codes deleted will I still be able to pass emissions testing?

 

i had the opposite code and that code was o2's low voltage which is lean condition with fuel and the opposite would be a rich mixture so you might try startin out to see if your filter is clean and your gettin enough air so on and so forth...

 

you should pass because you wont be throwing codes when they read it. unless they have a visual that in depth i think that you should be ok.