The CEL keeps coming back, always P0420 and only that code.
We did some research and it looks like the catalytic converter.
I found a lot of information on checking the O2 sensors and performed the following tests.
We used a plotting scantool (scantool. Net tool and OBDWiz).
The front censor indicated too lean when opening a vacuum line and too rich mixture when spraying starter fluid in the line as it should.
Just at normal idle the front sensor seemed okay, but the back sensor keeps oscillating. See the attachment.
If I understand things correctly Bank1 Sensor 2 should be a steady 0.5 volts.
If that is correct then is the oscillation caused by the catalytic converter failing to do its job or can it be something else?
If it is the catalytic converter, it might be easy to swap for a new one but I am concerned about the two bolts holding the front of the catalytic converter. They seem pretty small and have been "cooking" for over ten years. The heads might be easy to rip off.
Has anyone changed a catalytic converter and can you tell me if my concerns are valid?
Thanks in advance.
have the same problem?
Friday, February 23rd, 2018 AT 6:59 PM