Last night driving I got the dreaded p0420 code on my 16 Jeep compass. Things that make me think it eventually needs to be replaced: -i drove it for over an hour afterwards including on some hills, up to 5k rpm, up to 70mph no obvious signs of weak power etc, no obviously loud rattle -it had some misfires and spark plugs that went too long getting changed about a year ago so I probably shortened it’s life
On the other hand, it did occur right after a stretch of road with a lot of high frequency vibrations (lane construction that put those warning strips that shake your car into the lanes themselves) ivw read that could physically knock stuff loose inside the converter theoretically
I have a 15 hour drive back home on Sunday, my code reader is at home (I’m ordering a new one see if I can get it tomorrow so can watch the O2 levels live) , it’s my birthday and I’d much rather wait til I was back at my own mechanic (and my next paycheck) to go poking around into a bigger problem.
Thoughts?
Yes my plan is to have the O2 sensors checked and if it’s bad replace the cat.
That outcome is not uncertain.
My understanding of a bad cat is that there are two other outcomes, and these are the ones that concern me: the outcome where I pollute slightly too much for a couple weeks until I replace it. Or an outcome where I get stranded on a desert road as the cat gets blocked and the engine stalls out or does damage to itself. Those are important distinctions to me .
I’m also at Black Friday in a smaller town right before a weekend and missing days of work and pay on the other end while waiting here for an open mechanic isn’t ideal either but obvs better than the stranded one