Code P0420

BILL_THE_CAT

MEMBER
2007 SATURN VUE HYBRID
2.4L
4 CYL
2WD
AUTOMATIC
170,000 MILES

Wondering if any Saturn techs still here that might have some ideas about a P0420 low catalytic converter efficiency.

Thanks.

Tuesday, July 17th, 2018 AT 1:15 PM

1 Reply

ASEMASTER6371

MECHANIC
52,797 POSTS

Good evening.

The 420 is a code for the catatlytic converter. it needs to be replaced.

The precious metals inside are worn out and the downstream O2 sensor is reading the same as the upstream. The downstream O2 sensor should be a steady reading, not varying.

Roy

https://www.2carpros.com/articles/how-to-test-a-catalytic-converter