I am the third owner of a 97 Z28. The car has a magnaflow exhaust, along with high flow cats. The owner before me put on the exhaust and O2 simulator's, but the O2 simulator behind the cat (sensor 1 bank 2), occasionally does not function and causes the computer to throw a PO140. Until now I have been clearing it with a tech 2, but it is now happening more often and becoming irritating. My question is, what are good choices for O2 sims where I won't have to deal with this headache again. And where can I get them?

 

Sensor 1 bank 2 is the upstream sensor on bank 2, not the O2 sym which would be sensor 2

 

confused them bank 1 sensor 2