Originally Posted by Aced16
I have this annoying check engine light that wont go away. The car keeps triggering a P2C77. I went ahead and installed a new o2 since it was also getting a heater issue as well, and all that did was clear the heater issues. The code says something about post cat signal, anyone ever have this problem? Plugs are NGKs gapped accordingly with roughly 5k on them. I would appreciate any help!
Which o2 did you swap out? Pre-cat or post-cat? They do completely different things…Good news is, if it’s just a post-cat o2, your car should run OK. The post-cat o2 measures converter readiness, it’s the lambda o2 that you really need in functioning order.