Question

2005 Buick LaCrosse 3.8L with code P0420, what happens if you let the problem go?

Answer 1

P0420 Catalyst below effieciency

When the CK ENG LT is on the vehicle is in a emission violation ,If the vehicle is due for its inspection it fails and a registration permit is not given until the CK ENG LT is solved. The purpose of the CK ENG LT is to protect the catlytic convertor and the catalytic convertor is to protect the enviremont from harmful emission emmited into the atmosphere. If you let this problem go you just contribute to harmful emission emitted into the atmoshpere and the so called global warming issue.