Question

I got the engine code P0420 on my 2007 Chevrolet Suburban 8.3L V8 Can bad gas (87-91 octane) cause this problem (PO420 code)?

Answer 1

Hi there,

Sometimes the additives in the gas can cause the P0420 code. When I encounter this code I normally clear the code and fill it up at a different location. If the light comes back on with the same code, then it's time to replace the converter.

Comments

i replaced the Cats, and o2 sensors  still get p0420,  ford edge 2011, 3.5