P0420 and p0430

[Jarvis]

Has anyone ever had both of these codes at the same time before? Any information online points mostly to bad catalytic converters. Would trying all new 02 sensors work, or would they normally give different codes? The car has 153k miles

[sapote]

Use Veepeak Bluetooth obd dongle and OBDFusion phone app to generate a log file with these data with hot engine idling: rpm, engine temp, 4 O2 sensors, 4 fuel trims, MAF in g/s, and we can analyze the data.

[Jarvis]

Thanks for your response. I purchased Veepeak OBD dongle and was unable to get live data from OBDFusion app. Ended up going with Car Scanner app. I also watched this video to better understand what I was looking for. : https://youtu.be/aTNhxvyesPs?si=kT61vubVgGAjuK

It looks like my cats are bad after all.. with engine warm at idle and also at 2K RPM I was unable to see post cat 02 sensors stabilize around .8 volts.

[PSUEng]

Happened to me and I used it as partial justification for full SSV catted kit. New replacement headers may not even be available anymore and if they are, they are probably enormously expensive.

[sapote]

I purchased Veepeak OBD dongle and was unable to get live data from OBDFusion app.

Read and learn how to setup the tool to collect data in the log file, then upload the log .cvs file to Datazap to graph the data, then post its link here so we can analyze it.

https://www.e46fanatics.com/threads/how-to-read-obd2-engine-diagnostic-logs.1303572/