Heya Forumites, There's been weird happenings with my beloved CRV. It's a 2002, automatic, 2.4, with close to 190,000 miles. A few weeks ago, I was suddenly getting a boost in MPG on the highway, but not on city driving. In a few instance, my city driving mpg went down 4-6 mpg even though I drove the same route the same way. The highway driving is the oddest. I'm not getting anywhere close to mid-30's mpg by DWL around 45-50 mph, but I'm getting low 30's mpg by DWL at 70 mph. Strange, and I don't know if it has anything to do with my OBD code, which is the the main reason for this post. I checked my code, and it was P0420 which is the catalytic converter. It's been going on and off periodically since yesterday. The same code came up about 5 years ago, and I had the catalytic converter replaced. I've been reading up on some other forums and some people 1. don't do anything about it because it doesn't really mean anything 2. check and replace O2 sensors or 3. replace the catalytic converter. Can anyone shed some light on this code? I think the catalytic converter is still under warranty, but if it isn't a serious issues, I don't want to go to the trouble to replace it. Could the code be set off by something else other than the converter? Thanks in Advance. Jennie P.S. I'm not that much of a mechanic. I understanding of these parts is limited.