Misfire at idle once warmed up. throws a code 420 for catalytic convertor. catalytic convertor is 3 years old. no loss of power or gas mileage, no hesitation. new plugs , wires, computer flashed, o2 sensor are new. also compression was good on cylinders. originally had a code 300 but went away after replacing plugs and wires.
Mar 9, 2021 at 7:02 AM