Alright, I got the intermittent CEL for the pesky P0420 Catalyst System Efficiency Below Threshold (Bank 1). Generally, I can reset the CEL code and continue on; however, I think that I have a bad oxygen sensor. The sensor is operating at 100.2% efficiency...enough to throw me a code.
There are no performance issues when driving; however, when started I can smell gasoline vapors when the engine's cold and only exhaust fumes when warm.
I've been reading through SEVERAL postings on this and cannot figure out if my culprit is the front or rear mounted o2 sensor. The car only has 62K miles, so my thought is a front sensor. Does anyone have any suggestions before I crawl under to checkout the situation??