P0420 Cadillac -

Question

Can doing a 2 part fuel injection cleaner fix this code???

Answer 1

Hi there,

It's worth a try. The reason is because this code can appear due to fuel additives, un burned fuel and many other issues. I would suspect at the end of the day you will have to replace the converter because it's only bank 1 and not both banks, but I always clear the code and see if it comes back, if it does then the converter will likely have to be replaced.