Please Help! Unsolved Misfires in Cyl 2, 4 and 6

[Fu Manchu]

How would one know if they're cat is failing if there is no code for the failed cat? Also would it just require cleaning and bashing out?

The car would have a code for post cat sensor if it was rooted.
If the cat was blocked, the cat will get really hot. Infrared thermometer comparing entry and exit temps on the cat.

Cleaning cats can be done, but bashing them out is going to give you engine management butt hurt and no one wants that. It’s also environmentally irresponsible.

 

[Fu Manchu]

Hey everyone, i have just solved this in my 2010 SV6.... have replaced coils, plugs, chemically cleaned cats, cleaned intake valve carbon, still shutting down passenger bank 246. in the end.... it was my passenger side chain tensioner. so i did a full timing set and it has been smooth sailing ever since! ive also learned through all my hunting that its the same issue for drivers bank 135, however its caused by the PCV valve at the rear of drivers rocker cover blocking with carbon and causing an engine pressure issue. anyway, just wanted to let you know my rectification as it seems some stuck or spending to much chasing! cheers.

There is a free and simple PCV mod that should be done. It wasn’t rectified until the last of the VF’s.

https://forums.justcommodores.com.au/threads/vz-and-ve-alloytec-pcv-problem-fix.279039/

Clean out all the PCV hoses/pipes too.