GenVibe - Community for Pontiac Vibe Enthusiasts

Hi. Not sure if I am posting this in the right spot - I have a 2005 Vibe base. I was getting a p0420. I replaced the upstream oxygen sensor and the p0420 code came back. I replaced the downstream oxygen sensor (Denso) , the p0420 is gone, but now I am getting a p2238 code. Can anyone tell me what direction I need to go now? I'm thinking maybe it's the part? but not sure. TIA.

Typically P0420 is due to a bad cat, and not a bad o2 sensor. That code actually says the o2 sensors are working, in that they detected the efficiency of the cat is below the established threshold.

As for the code you now have, P2238, based on what you've done, I would lean towards the first o2 not being plugged in, or a broken wire. Basically, that code says the first sensor has no reading.

https://www.engine-codes.com/p2238_toyota.html

You can pick up a cheap bluetooth code reader on amazon/ebay. $10 for the reader, and $5 for the TorquePro app, and you can actually read darn near any sensor the car has and verify the live data.

Thanks. I'll check the wiring.